Roads Feb-Mar 09_1 - Australian Asphalt Pavement Association

Contents32 From the AAPA CEO34 From the AAPA Chairman35 AAPA National Technology Committee36 Asphalt Proficiency Testing Report Released42 Repair of Asphalt Parking Lots and Driveways46 Queensland Department of Main Roads /AAPA Strategic Alliance50 Sprayed Sealing Practice in Australia55 Green Roads are Cool Roads – Warm Mix Asphalt57 AAPA Training Centre Releases Training Calendar for 200960 AAPA Training Courses – Topics on Offer62 Safe Handling of Hot Bitumen63 Asphalt NewsROADS FEBRUARY/MARCH 2009 31

ASPHALT REVIEWFROM THE CEO’s DESKI was sitting at my desk thinking aboutwhat I should say in this edition ofAsphalt Review.For the first edition for the year it isnormal to wish everyone all the best for2009, and I certainly wish you well forthe coming year. It is also normal to talka little about the previous year and thensay how successful we hope the next yearwill be. But while 2008 may have been asuccessful year for many AAPA membersand our clients, the economic crisis thatstarted in the US will certainly make2009 less certain.Already the broader constructionindustry is experiencing problems withsome commercial and residential developmentseither being stalled orabandoned. This will have an immediateimpact on some companies.Importantly, it may also have an impacton the ability of companies to plan withany certainty for future staff, equipmentand materials needs.The year may therefore have somesignificant challenges for our industry,the flexible pavements industry. Butbefore looking at the possible impact ofthe current situation, let’s have a brieflook at 2008. It was certainly asuccessful year for many companieswith a number of major projects beingopened well ahead of schedule, one ofthese being EastLink in Melbourne.That project particularly comes tomind for me as I have just receivedseveral copies of a colourful, glossybooklet titled “Eastlink: Melbourne’sMotorway Masterpiece”.This booklet was published by theVictorian Government, Southern andEastern Integrated Transport Authority,ConnectEast and World Highways soyou would expect it to promote thepositives of the project – and it certainlydoes that. But forgetting the hype, thebooklet highlights an example of thehigh quality road projects we can deliverin Australia, projects that bring withthem a wide range of short and longterm economic and social benefits.According to the publication, theEastLink project generated an estimated$15 billion boost to the local economyand 14,000 jobs during its constructionand operation. It is also expected thatthe road will create 6,500 ongoing jobs.A major road such as this also providesfast and safe transport for goods andpeople and long term economic growth.The booklet also highlights theenvironment and community benefits ofJohn Lambert,CEO, AAPAsuch a well executed project. Theseinclude the preservation of the MullumMullum Valley and the creation of significantwetlands and public parks. Over3.5 million native trees and shrubs wereplanted as part of $50 million spent onlandscaping. Major roads such as thisalso reduce the amount of fuel used totransport goods resulting in overalllower greenhouse and other emissionsfor each tonne/kilometre of goods transported.And added to this is apedestrian/cyclist route that followsEastlink.And of course, AAPA members playeda major part in achieving thisoutstanding project which was deliveredAsphalt Review reports on the flexiblepavements and bituminous surfacingindustry in Australia and New Zealand. Itis published by ROADS Magazine onbehalf of Australian Asphalt PavementAssociation Limited (ABN 31 000 770123), a non-profit organisation formed topromote the economic use of asphalt andother bituminous bound products basedon sound technical and commercialgrounds for the benefit of its members,their customers and the community.Articles in Asphalt Review may bereprinted provided acknowledgement isgiven. Contributions of a news ortechnical nature on all aspects of asphaltand bituminous surfacing are welcome.ADMINISTRATIONAAPA Head OfficeLevel 2,5 Wellington StreetKew, Vic 3101Tel: (03) 9853 3595Fax: (03) 9853 3484Email: info@aapa.asn.auWebsite: www.aapa.asn.auAsphalt ReviewEditor: Rex PannellEmail rex.pannell@halledit.com.auAdvertising: Yuri MamistvalovEmail yuri@halledit.com.auTel: (03) 8534 5008The Asphalt Review Magazine,prepared by the Australian AsphaltPavement Association (AAPA) is nowalso produced as a supplement in theROADS magazine. To gain access toa broader readership, AAPA hasundertaken to publish within ROADS,but its content will maintain theuniqueness and specialty focus onflexible pavements that AsphaltReview has provided for over 25years. Availability of this and futureissues of the Asphalt Review willcontinue via the AAPA web site:www.aapa.asn.au in addition to itsinclusion in ROADS magazine.The publishing schedule is:February-March; June-July; andOctober-November.32 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWfive months ahead of schedule. In fact, tomost of the community, the mostoutstanding feature of this road is itsbeautiful ride quality, a standardachieved by AAPA members who laid1.25 million tonnes of asphalt producedin plants that have left no discernableimpact on the environment.My reason for mentioning EastLink isnot just to highlight this project.EastLink is but one example of how roadprojects right across Australia canachieve short, medium and long termeconomic, social and environmentalbenefits for our whole community. Thereare indeed many other projects bothlarge and small such as the Tugun Bypassin Queensland that have been completedto a very high standard to the benefit ofthe whole community.But is the success of these projectsrelevant to 2009?For those of us involved in the roadconstruction and transport industries weunderstand the importance of aneffective and efficient road network.Without an integrated, safe and wellmaintained road network, society as awhole will suffer. It is essential that theroad infrastructure is continuallydeveloped and maintained. Even duringtimes when finance is tight, thecommunity will still expect the transportnetwork to be maintained and developed.Infrastructure projects provide ameans of injecting funds quickly andeffectively into communities. Whether itis a major new road construction ormaintenance of local roads, money spenton the roads quickly goes back into thecommunity. The multiplier effect is alsohigh, multiplying its value over a widerange of suppliers and service providers.From the suppliers of road constructionequipment to the corner shop thatprovides workers with their lunch, roadprojects support employment andeconomic growth. The wages paid toasphalt workers also are used to buyother goods from children’s footballs toa night out with their partner. Moneyspent on roads is certainly far better thangiving money directly as handouts toindividuals to enable them to buy moreimported commodities with only a smallmultiplier effect.Governments around the world arelooking at ways to stimulate theireconomies. My advice to them is to setaside considerable amounts for roadconstruction and maintenance. This willensure that roads infrastructurecontinues to support economic growththrough safe and efficient transport.Equally it will provide direct economicstimulus to the Australian economy bymaintaining both direct and indirectjobs to many thousands of Australians.Industry will also be able to maintain itscurrent high standard of expertise andwill be able to offer young entrants intothe construction industry the trainingand experience to support our transportsystem into the future.Of course industry must also play itsrole in these difficult times. Industrycannot just sit back and expectgovernment to give it taxpayers’ money.Instead, industry must ensure that itcontinues to maintain its high level ofskills and quality. It must also ensure thatsafety and environmental standards arealways maintained at the highest level.AAPA Training offers one way that theindustry, clients and consultants canmaintain the high quality that theAustralian community has come toexpect. This edition of Asphalt Reviewincludes the 2009 AAPA Trainingcalendar and I recommend that allparticipants in our industry review thecurrent courses and either attend or sendstaff to those courses relevant to yourneeds.These courses are maintained to a highstandard and are regularly reviewed.New courses are also developed as appropriate.To further ensure the relevance ofthese courses AAPA, as announced by theAAPA Chairman, Louis Nucifora, will bereviewing the AAPA Training Centrestrategic plan to ensure it continues tomeet AAPA members’ needs.AAPA Training also offers customisedcourses and I recommend that youcontact the Training Centre to discussyour needs.Post graduate courses in thepavements industry are also availablethrough the Centre for PavementEngineering Education (CPEE). TheAAPA website has a link to CPEE forfurther information.One certainly bright event for 2009 willbe the AAPA International FlexiblePavements Industry Conference. Thiswill be the 13th conference and will beheld at the Marriott on the Gold Coastbetween 11 and 14 October 2009. It willprovide an opportunity for Australianand overseas experts to discuss thecurrent and future direction of theflexible pavements industry.The conference will include manypapers relating to technical issues,regulations and standards. These willinclude papers relating to asphalt,bitumen and sprayed sealing.Environmental issues will alsocertainly be discussed as more and morewe are all expected to play our role inreducing environmental impacts. Thisincludes reducing greenhouse gasemissions as well as impacts on nativeflora and fauna. Another theme which Iam sure we cannot forget is the impact ofthe current economic situation.There is a separate note on theconference in this edition of AsphaltReview and I encourage all of you to readit, and if you have a paper that you wouldlike to present, then please let theconference organisers know.Other articles in this edition address arange of topics. These include the secondpart of Walter Holtrop’s excellent paper,Sprayed Sealing Practice in Australia.This paper provides a valuable outline ofthe general philosophy behind selectinga particular type of sprayed treatment.Other papers discuss warm mix asphaltand repair of asphalt parking lots anddriveways. The Queensland MainRoads/AAPA Strategic Alliance anddetails of the 2009 AAPA Trainingcourses are also highlighted.Asphalt Review also reminds us aboutthe effect of skin cancer and the sun,building on the paper presented in thelast edition and there are a range of otheritems of interest to our industry.Before closing this note, I mustcomment on the recent fires and floodsthat have hit eastern Australia. The startof 2009 will be remembered for a verylong time by all of us as one of the worstin history. With bushfires in Victoriaand floods in Queensland and NSWthere are few people not affected. But itis times like this that we all recognizethat as Australians we are all prepared tohelp each other in times of need.I guess there are people in our industrywho are directly affected and to themthere is nothing I can say that the wholecommunity has not said before. But Ihope that you gain strength from the waythat Australians across the whole of thecountry and those overseas haveexpressed their support in both wordsand deeds.For the rest of us, I am sure we will alldo that little extra that we do whenContinued over pageROADS FEBRUARY/MARCH 2009 33

ASPHALT REVIEWFROM THE AAPA CHAIRMANAnother year has flown by, a successfulyear for our industry with several majornew roads opening and sales of bitumenand flexible pavements growing in somestates.But there is now a lot of attention onthe world’s economy and this will havean impact on all industries in Australia,including ours. The year 2009 will be aninteresting year with both opportunitiesand challenges.We know that roads are a critical partof the community’s infrastructure,providing safe and effective transportcorridors for people and goods,Continued from previous pagepeople are in need. This will includeworking to repair roads damaged byfloods and fire, emphasising theimportance of our industry to communication,transport and safety.However, I am sure it will also includemany people from our industry givingtime and effort as well as donations tohelp those affected.These events combined with thecurrent economic situation havecombined to make for a very unpredictablestart to 2009.So will 2009 be a good year or a pooryear for our industry?There is a Chinese curse “May youlive in interesting times” and itcertainly looks as though 2009 will be“interesting times”.But road construction and maintenanceis a sure way to support theAustralian economy, providing a widerange of short, medium, and longterm benefits to the whole of thecommunity. We therefore need toremind our politicians of thiswhenever we get the chance.Knowing the community demandfor effective and safe transport infrastructureand the economic benefits Iam confident that 2009 will be asuccessful year for our industry. Butthroughout this year we must all bevigilant and maintain the highstandards of workmanship, safety andenvironment protection that typify theflexible pavements industry.Good luck for 2009 and I lookforward to working with all of youduring these interesting times.contributing significantly to sustainableeconomic and social growth. Funding ofnew roads also provides effective andquick means of injecting financialsupport into communities, with significantflow on into a wide cross section ofthe community. I am therefore confidentthat the Federal and State Governmentswill continue to support road projects.However, the old saying “a stitch in timesaves nine” applies to road maintenanceand I encourage road authorities tocontinue to support needed maintenanceof our existing roads through thedifficult economic times ahead.Road projects have a direct economicbenefit to the community and a significantmultiplier effect. This year shouldtherefore be seen as a time to supportroad infrastructure for the benefit of thewhole community.While there is optimism for theflexible pavements industry, it does notmean that AAPA members can becomplacent during 2009. There willcertainly be economic challenges. Thesemust be met directly focusing onefficiencies with continued adherence toquality. To do otherwise will just lead tofailures for both our industry andclients.Companies and government agenciesalike cannot slacken their commitmentto our staff. Staff are our most importantasset. Equally, everyone working in ourindustry must work to achieve qualityoutcomes as well as maintaining thehighest standards for work place safety.In my company we are holding a “Backto School Day” early in the New Yearwhich includes the review of high-riskscore incidents and to reinforce oursafety priorities. This is just one way wecan support the achievement of workplace safety.To support quality outcomes andsafety, all staff must be appropriatelytrained. AAPA is therefore once againoffering a comprehensive range oftraining courses as well as a service todevelop and deliver customised courses.These courses are for new entrants,experienced workers and consultants.They are equally relevant to clientgroups.Courses cover subjects from the safehandling of bitumen to the effectiveapplication of asphalt and details areLouis Nucifora,Chairman, AAPAcontained in this edition of AsphaltReview. However, AAPA recognises thatto be effective these courses must bemaintained at a high standard. Theymust address current technologies,standards and regulations. They mustalso be able to be delivered in differentways to meet members’ needs. Forexample, some companies may wish todeliver these courses to their own staffwhile others may prefer to attend anAAPA run training course.AAPA constantly updates its coursesand this coming year will update itsstrategic plan for AAPA Training. Thiswill ensure that AAPA Trainingcontinues to meet the current and futureneeds of its members and clients alike.The flexible pavements industry mustcontinue to support the push for developmentand implementation ofconsistent frameworks for standards.Consistency in standards will assist ourindustry to achieve high qualityoutcomes, profitability and workplacesafety. Through 2009, AAPA willtherefore continue to work withAustroads and road authorities toachieve consistent standards.2009 promised to be a unique yearwith many challenges and opportunities,but the fires and floods that have hiteastern Australia will impact on all of us.Although I look forward to a challengingand exciting year for our industry I alsoextend my best wishes and those of theAAPA Board to all those affected and tothe many people in our industry who arehelping them. It is times like this that werecognise the good in people, the way somany give so freely to help those in need,whether it is by giving time or donations.Finally I look forward to workingtogether to meet the challenges of 2009and beyond.34 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWAAPA NATIONALTECHNOLOGY COMMITTEEAAPA’s National Technology Committee, currently chairedby Peter Armstrong of Fulton Hogan, boasts over 20 yearsof distinguished contribution to technical advancement andcontinuous performance improvement of the flexiblepavements industry in Australia.While engaging in both co-operative and singular researchprograms over that time, as a peak industry technical bodyit focuses on securing, on sound technical grounds,nationally consistent, improved pavement outcomes in theinterests of AAPA members, their clients and the community.It recognises it has a strong role in ensuring deliverablesthat enhance the reputation of the total road industry,members, members’ products and services, and the associationitself.To these ends, its history demonstrates the industry’scommitment to engage with, support, contribute knowledgeand ideas to and influence its major client groupings throughco-operative linkages with Austroads, the state road authorities,ARRB Group and local government. As a result, thetechnical contribution of AAPA on behalf of its members issought by road authorities and research organisations.In the mid-80s, AAPA formalised liaison between industrymembers and road authorities when the then AAPA R&DCommittee, led by AAPA Technical Director Ian Rickards,established the AAPA R&D Advisory Group. This groupcomprised industry and client members to provide directionand progress AAPA’s initial three-year research and developmentprogram. The simple objective of this program wasto develop the means to verify the performance of asphalt toprovide confidence that the properties used in asphaltpavement thickness design were appropriate. This objectivehas certainly been achieved.A couple of demonstrable points of the history of industrycommitment are noteworthy here. The contribution byIndustrial Process Controls (now IPC Global) through AAPAis one. IPC responded to industry’s request for affordabletools to manufacture homogeneous samples and measure theperformance related characteristics of asphalt. This workresulted in the development of world class tools which havebeen acquired widely across Australia. Similarly, it is of greatcredit to the asphalt industry, through AAPA, that theirtechnical personnel were sponsored to undertake and leadROADS AdvertisingTo reach the decision-makers in the roads field, consideradvertising in ROADS. For information on advertisingrates, please contact Yuri at Hallmark Editions,Tel (03) 8534 5008 or email yuri@halledit.com.auPeter Pezet from Fulton Hogan preparing a sample for testing.the initial research and development that has enabled theadvances in asphalt technology we all enjoy today.The evolution of the AAPA R&D Advisory Group into theNational Asphalt Research Committee (NARC), which alsoincluded members from the Austroads Pavement ResearchGroup, occurred in the early 1990s. For much of thefollowing decade NARC was led by John Bethune who hadtaken over from Ian as AAPA Technical Director. A similargroup comprising AAPA and Austroads was also establishedto work in the areas of binders and sprayed surfacing. AAPAinput to this committee, the National Bituminous SurfacingResearch Group (NBSRG), was led by Walter Holtrop.Then in 2004, a revised strategic plan within Austroadsgave rise to a new structure of technical and review forumsfor the pavement industry. Today, AAPA technical input tothe Austroads Committees is maintained by its representationon the successor to NARC, the Asphalt ResearchReference Group (ARRG), the Bituminous SurfacingsResearch Reference Group (BSRRG) and the ReferenceGroup’s parent body, Pavement Technology Review Panel(PTRP).Since the formation of AAPA, members have been able tolead the development of technology that has resulted in ahighly professional industry, producing road surfaces thatmeet the ever increasing demands of the Australiancommunity. Through the AAPA National TechnologyCommittee and its State Technical Committees AAPA willcontinue to support the flexible pavement industry. AAPAwill also continue to provide an avenue through which all itsmembers can contribute.In the next edition of Asphalt Review details of thecommittee’s current program will be provided along with alisting of recent outputs from ARRG and BSRRG and currentemerging issues.ROADS FEBRUARY/MARCH 2009 35

ASPHALT REVIEWASPHALT PROFICIENCYTESTING REPORT RELEASEDAs part of its drive to support consistency and accuracy AAPA funded, through its National TechnologyCommittee, a nationwide comparative assessment across the laboratories of member companies andother industry participants. This study compared the consistency, accuracy and reliability oflaboratories by requiring each laboratory to undertake tests for bitumen content and aggregategrading. Each laboratory tested these two parameters in accordance with eight different test methodsproviding the opportunity to assess the consistency of both the laboratories and the test methods.Chairman of the AAPA National Technology Committee, Peter Armstrong, was the Project Coordinatorfor this program. Proficiency Testing Australia (PTA) performed the analysis of the results obtained inthe program for AAPA and the report on the project was released by the AAPA Board at its November2008 meeting. Copies of the report have been forwarded to each participating location. MrArmstrong was well satisfied with the program, stating; “The high level of consistency and competenceof the participating laboratories was demonstrated by the results and gives us great confidence in theindustry’s quality control reliability.” The program also noted that there was no statistically significantdifference for bitumen content and grading obtained by the various test methods. This study was partof AAPA’s ongoing precision testing program, the next phase of which is to examine the AsphaltFatigue Test. The Asphalt Proficiency Testing Report follows.This report summarises the results of aproficiency testing program covering aseries of tests on asphalt.The members of the AustralianAsphalt Pavement Associationconducted the testing program.Proficiency Testing Australia (PTA)performed the analysis of the resultsreported for this program.The aims of the program were twofold:i. To assess the consistency and competencelevels of the laboratories toperform the tests and the consequentlevel of confidence able to be generatedin the results produced by the asphaltsuppliers.ii. To compare and analyse the resultsfor bitumen content and aggregategrading obtained from the eightdifferent Australian test methods.Project SummaryThrough August and September 2007,the Australian Asphalt PavementAssociation (AAPA) conducted anextensive nationwide analysis andtesting program across laboratories ofits member companies to assess theirability to consistently, accurately andreliably undertake two specific tests thatare important for customer and supplierconfidence in the quality of the asphaltthe companies manufacture.The two tests examined were forbitumen content and for aggregategrading. Tests results were provided by81 Australian laboratories, each ofwhich was randomly allocated a uniquecode number to enable confidentialityfor the participating laboratories to bepreserved. Reference to the laboratoriesin the report is thus via the allocatedcode.The laboratories were requested toperform the tests according to their ownparticular accredited methods. Thuseight different test methods, derivedfrom the local use of differing StateRoad Authority, Australian Standardsor Austroads test methods, wereemployed in the program.The analysis of the results reported inthe program was undertaken for AAPAby Proficiency Testing Australia (PTA).The homogeneity of samples supplied tothe participating laboratories wasverified by tests undertaken by FRHGroup Pty Ltd to satisfy the conclusionbeing drawn that any results lateridentified as outliers could not beattributed to variability of sampletested.The next proficiency exercise in theAAPA series is to be conducted on theAsphalt Fatigue test, giving rise to afurther technical report in due course.Features of the Programa) A total of 94 laboratories were sentsamples for the program. Of these 94laboratories, 13 did not return results intime for inclusion in the final report.b) Participating laboratories weregenerally supplied with one sample.c) The following tests were performedby participants on the samples:• Bitumen content• Aggregate grading determination.d) The samples were analysed forhomogeneity by FRH Group Pty Ltdusing both the Australian Standardmethod AS 2891.3.3 and the Austroadsmethod AG:PT/T234. Based on theresults of this homogeneity testing itwas concluded that the samples weresufficiently homogeneous. Therefore,any results later identified as outlierscould not be attributed to any signif-36 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWicant sample variability (see AppendixB).e) Laboratories were requested toperform the tests according to theiraccredited methods and the“Instructions to Participants”, and torecord their results on the accompanying“Results Sheet”, both of whichwere distributed to participants with thesample (see Appendix C).f) Each laboratory was randomlyallocated a unique code number for theprogram to enable confidentiality ofresults. Reference to each laboratory inthis report is made by its code number.Please note that some laboratoriesreported more than one set of resultsand, therefore, one code number (withletter) could appear several times in thesame data set.Format of the AppendicesAppendix AAppendix A lists all the results reportedby the participating laboratories foreach test. It contains:• Calculated robust z-scores, ordered z-score charts and a table of summarystatistics (including number ofresults, median, normalised IQR,robust CV, minimum, maximum andrange) for the bitumen contentresults.• The number of results, median andnormalised IQR for the aggregategrading results. Z-scores have notbeen calculated for the aggregategrading results. Instead, upper andlower limits were determined bymultiplying the normalised IQR by 3.Any results reported outside of theselimits have been classified as anoutlier result. Scatter plots displaythe distribution of results reported.Appendix BAppendix B contains details of thehomogeneity testing.Appendix CAppendix C contains a copy of the“Instructions to Participants” and the“Results Sheet” supplied to participants.Design of the ProgramThe need for regular proficiency studieson asphalt tests was raised at a meetingof the AAPA National TechnicalCommittee and this study is the first ofan ongoing series of AAPA proficiencyexercises. AAPA intend to regularlyperform proficiency studies on testscurrently required by the variousasphalt specifications.All Australian laboratories accreditedby NATA to perform the specific testswere invited by AAPA to participate inthe exercise.The confidentiality of results wasensured by randomly allocating aunique number to each participatinglaboratory.The instructions to participants wereprepared by AAPA/Industry members toensure the tests were performed to arelevant standard and all informationrequire to analyse the data wasavailable.38 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWThe samples were prepared by oneAAPA member company who alsoperformed the homogeneity testing.The analysis of the data wascontracted to Proficiency TestingAustralia.Outlier ResultsRobust z-scores have been used toassess each laboratory’s testing performancefor bitumen content. Whencalculated from single results, z-scoresare used to detect excessively large orexcessively small results in comparisonto the consensus value (the median).Any result with an absolute z-scoregreater than three (ie 3) isclassified as an outlier. For furtherdetails on the calculation and interpretationof robust z-scores, please see theGuide to Proficiency Testing Australia(2006).For aggregate grading, any resultsreported that are outside the upper andlower limits are classified as outliers.Table A summaries the resultssubmitted by participants for theprogram.Laboratories who reported outliersare listed in Table B. Any laboratoriesthat reported outliers who areaccredited for the specific test areencouraged to investigate the cause(s)of the outlier(s).Technical CommentsMethod ComparisonThe most common method used by theparticipants in this program was theAustralian Standard method, AS2891.3.3, with 26 laboratories usingthis method. Twenty four laboratoriesused QDMR Q308A, 20 laboratoriesused AS 2891.3.1, 10 laboratories usedAustroads AG:PT/T234, 7 laboratoriesused WA 730.1, 5 laboratories usedQDMR Q308D, 5 laboratories usedDTEI MAT - TP470 and 2 laboratoriesused DTEI MAT - TP473. No laboratoriesreported using the methods AS2891.3.2, RC 210.05, RC 210.06, RTAT607 or RTA T609. There were 2laboratories (codes 2858 and 9480) thatdid not specify the method they used fortesting.Prior to calculating z-scores andupper and lower limits for the results,an analysis of variance was performedon both the bitumen content andaggregate grading results to determineif there was a difference between thedifferent methods used for testing byparticipants. The results of this analysisshowed that there was no significantdifference between the differentmethods used. Therefore, the resultswere pooled across all methods whencalculating z-scores for the bitumencontent results and upper and lowerlimits for the aggregate grading results.Bitumen ContentTwo laboratories reported outliers forbitumen content. These were laboratories305 and 6951. In addition, |z|scores > 2 were also obtained by laboratories804, 1528, 2988A, 3556, 4777B,6057B, 7031B, 7513B and 9898. Whilenot classified as outlier results, anylaboratory that obtained a |z| score > 2is also encouraged to review theirresults.Aggregate GradingUpper and lower limits were set for eachsieve size, with any results outside theselimits considered outliers. Scatter plots(see Appendix A) highlight the upperand lower limits and display the spreadof results. Upper and lower limits foreach sieve size are presented in Table C.For sieve size 13.2 mm, laboratory8448 reported an outlier. For sieve size9.5 mm, outliers were reported bylaboratories 804, 3064B, 4732, 4777Band 8448. For sieve size 6.7 mm, anoutlier was reported by laboratory 804.No outliers were reported for sievesizes 4.75 mm and 2.36 mm. For sievesize 1.18 mm, outliers were reported bylaboratories 5020B and 7513A. Nooutliers were reported for sieve size0.600 mm. Laboratory 1528 reportedoutliers for sieve sizes 0.300 mm, 0.150mm and 0.075 mm.ConclusionsThe conclusions able to be drawn fromthe analysed test results aresummarised as:i. Of the 81 participating laboratories,only two were reported as outliers in themeasurement of bitumen content andonly eight were reported as havingoutliers on one or more of the ten sievesizes used in the aggregate grading.ii. There was no statistically significantdifference in the results for bitumencontent and grading obtained from thevarious test methods employed in theprogram.The project has thus demonstratedthe validity of holding full confidence inbitumen content and aggregate gradingresults obtained from the laboratoriesof the Australian asphalt producers.References[1] Guide to Proficiency Testing Australia –2006. (This document is located on thePTA website at www.pta.asn.au, under“Documents”).40 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWREPAIR OF ASPHALT PARKINGLOTS AND DRIVEWAYSThis article is featured courtesy of the US Asphalt Institute.Many owners of asphalt driveways andparking lots have found, at some pointin time, that their pavements needrepairs. The reasons for the problemsvary widely. Lack of maintenance, poordrainage, inadequate thickness,accumulated wear-and-tear, and othercauses all contribute to the eventualneed for significant repairs. Some of thecommon problems encountered includepotholes, deteriorated joints, and structuralfailures.PotholesPotholes are bowl-shaped holes thatresult from the localized break-up of thepavement. They are typically caused bythe continued deterioration of othertype of distresses, such as segregation,raveling, alligator cracking, or failuresat joints or patches.(exceeding 6 inches), the new mixshould be placed in two layers. Eachlayer of new asphalt mix should becompacted thoroughly. Adequatecompaction is critical for preventingshoving or deformation of the newmaterial and to prevent water fromentering the pavement.For larger sites with numerouspotholes to be repaired, spray-injectionpatching may be practical. Thistechnique uses a specially-equippedtruck having an emulsion tank,aggregate bin, and a high volumeblower with an injection head.Compressed air is used to remove looseasphalt material and any debris. A hotemulsion tack coat is applied and thenthe aggregate and hot emulsion areblown into the patch. Compaction isachieved by the forced air as the mix issprayed into the patch.Deteriorated JointsPoorly constructed joints greatly reducepavement life. Joint failure starts whenair, water, and contaminants enter thejoint through segregation, poorcompaction, or lack of bonding betweenadjacent mats. If the distress is notedsoon enough, a seal can be applied tocorrect the flaw. If the deterioration isnot addressed, potholes may form andthe problem is more difficult to correct.Repair is then similar to that describedfor potholes.Structural FailuresMany commercial pavements sufferstructural failures as a result of loadrelateddeterioration. These problemsusually show up initially as “alligatorcracking,” a form of fatigue cracking.These cracks appear on the surface ofthe pavement as a series of interconnected,small blocks resembling analligator’s skin. This cracking occursunder repeated traffic loading and iscaused by weak spots in the subgrade,too little pavement thickness, excessiveloading, or a combination of thesecontributors.Potholes should be permanentlyrepaired by removing the failed materialto the depth necessary to reach firmsupport, including removing part of thesubgrade if necessary. Drainage mayhave to be installed if water in thepavement is contributing to the failure.The area to be removed should extendbeyond the visibly damaged material toassure that solid material remains. Tofacilitate compaction of new material,the cut-out should be square-edged andrectangular-shaped.The vertical edges and the bottom ofthe cut-out should be tacked. Then thehole should be filled with dense-gradedhot mix asphalt (HMA), if available. IfHMA is not available, a cold patchingmix can be used. If the hole is deepAAPA SEEKS ANEXECUTIVE OFFICERFOR NSW BRANCHThis is an exciting position thatgives the right candidate the opportunityto work with members to helpdrive the flexible pavement industryin NSW. The position will suit a selfstarter with broad relevant administrativeand technical skills.The position may be three, four orfive days per week depending on thecandidate and the salary willrecognise the importance of the role.If you are interested in thisposition, a job description is availableon the AAPA website or call JohnLambert, CEO, for a confidentialdiscussion. Phone: (03) 9853 3595/0419 822 114.If alligator cracking is allowed toprogress, it can become a full structuralfailure. Pieces break away and potholesform. Moisture enters the subbase andpavement support is lost. When thisoccurs a full-depth repair must be done.Many commercial pavements failbecause the pavement is simply too thinto carry the loads. Practically all parkinglots are subjected to some truck traffic;delivery vehicles and garbage trucks area fact-of-life. Building a pavement withsufficient thickness to handle thesevehicles is a wise investment.42 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWWhen a base failure occurs, thefailed asphalt must be removed, theunderlying material stabilized, andthe pavement replaced. The cause ofthe failure must be identified andaddressed. If the problem is a softspot in the subgrade, this weaknessmust be fixed. If the problem was dueto too little pavement thickness, therepair area will have to be undercut toallow room for additional thickness tobe placed.Other DistressesOther types of pavement problemscan be found in commercial andresidential pavements. Theseconcerns can include raveling,rutting, and slippage failures.Raveling is the loss of aggregateparticles from the surface of thepavement. Raveling can occur whenthe asphalt binder hardens and losesits grip on the stone or when a poorquality mix is used. If caught early,raveling can be addressed by sealing.If the condition is severe, an HMASKIN CANCER AND THE SUNIn the last edition of Asphalt Review,Kay Coppa from the NSW CancerCouncil highlighted the significanteffects of skin cancer. In the middle ofsummer it is timely to remindourselves of this and to ensure that atwork and at leisure we protect ourskin from exposure to the sun’sradiation.We all remember the CancerCouncil’s slogan “Slip, Slop, Slap” –slip on protective clothing, slop onsunscreen and slap on a hat. Now wemust also remember to Seek shadewhenever possible and Slide onsunglasses.At work or at leisure, protectyourself and your family fromexposure to the sun.For further information go to theCancer Council website www.cancercouncil.com.au.This site has a largeamount of information and thefollowing documents relating toworkplaces may be downloaded:• Checklist - A guide toimplementing better practice insun protection in the Workplace;• Sun Safety At Work: Policy onprotection from Ultravioletradiation for Outdoor Workers;and• The Radiation Protection Standardfor Occupational Exposure toUltraviolet Radiation (2006)Other relevant documents that maybe obtained from the Cancer Councilinclude:• A workplace sun protection policyguide;• Skin cancer and outdoor work - aguide for employers• Skin cancer and outdoor work: aguide for working safely in the sun.The dangers of contracting skincancer have also been highlighted bythe Chairman of the Australian Safetyand Compensation Council, BillScales.Mr Scales focused on Australia’srate of skin cancer while speaking atthe release of Guidance Notes for theProtection of Workers from theUltraviolet Radiation in Sunlight.“Australia has the highest rate of skincancer in the world. Adopting saferwork practices when workingoutdoors not only has a positiveimpact on employees, but can alsolead to significantly reduced organisationalcosts and economic costs.Everybody should be SunSmart whenat work.”The guide was released by the ASCCin conjunction with Cancer CouncilAustralia. The National Skin CancerCommittee Chairman, Craig Sinclair,says at least two in three Australianswill be diagnosed with skin cancerbefore the age of 70.Copies of the guide are available forfree download from the ASCC websiteat (www.ascc.gov.au).overlay or surface treatment isneeded.Ruts in asphalt pavements arechannelized depressions in the wheeltracks.Rutting results fromconsolidation or lateral movement ofany of the pavement layers or thesubgrade under traffic. It is caused byinsufficient pavement thickness; lackof compaction of the asphalt, stonebase or soil; weak asphalt mixes; ormoisture infiltration. If rutting isminor or if it has stabilized, thedepressions can be filled and overlaidwith HMA or a surface treatment. Ifthe deformations are severe, therutted area should be removed andreplaced with suitable material.Slippage cracks are crescentshapedcracks or tears in the surfacelayer(s) of asphalt where the newmaterial has slipped over the underlyingcourse. This problem is causedby a lack of bonding between layers.The lack of bond may be because atack coat was not used to develop abond between the asphalt layers orbecause a prime coat was not used tobond the asphalt to the underlyingstone base course.The lack of bond can be caused bydirt, oil, or other contaminantspreventing adhesion between thelayers. All of the area exhibiting the“stretch marks” will need to beremoved. Make sure that the existingpavement is clean and dry afterremoving the failed layer. Then applya tack coat to glue the old and newmaterial together. Place and compactthe new layer(s).Additional AssistanceThis article provides general guidancefor repair of commercial andresidential asphalt pavements.Depending on site conditions, therepairs may need to be site-specific.More details on identifying andrepairing pavement problems can befound in the Asphalt Institute’s publications,(MS-4) The Asphalt Handbookand (MS-16), Asphalt in PavementMaintenance.AAPA currently has a range ofAsphalt Institute publicationsincluding the above - see page 62.44 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWQUEENSLAND DEPARTMENT OFMAIN ROADS/AAPA STRATEGICALLIANCEBy Rob Vos, AAPA Regional Executive QueenslandSince its inception in 2001, the QDMR / AAPA Qld Strategic Alliance has shown a new way tointegrate the energies of a State Road Authority and industry to deliver speedy resolution to commonproblems, to proactively and collaboratively seek innovative solutions and to work together on win-winoutcomes. Acknowledging that there is always scope for improvement new short term goals are tofurther embed this alliance approach across industry and Main Roads, harnessing the collectivegoodwill for the challenging times ahead and above all, seeking better ways to preserve and maintainthe valuable road network of Queensland.Strategic Alliance formedSigned in 2001 by the then Director-General, Steve Golding, the AllianceAgreement provided the principles andmeans to drive better outcomes forflexible pavements in the State, coveringboth the scope and the requiredoperating conditions. From thebeginning it was agreed that the activitiesmust exclude the commercial/contractual issues of AAPA membersand Main Roads rather concentratingon high level strategic issues as well asaddressing industry wide aspects suchas standards, systems, planning,resource availability and direct commonbenefit projects.ManagementThe Strategic Alliance is under thecontrol of a board of directors whichmeets at least four times annually.Current board members are the MainRoads Deputy Director General, LesFord and General Manager –Engineering & Technology Ian Reeveswith AAPA Queensland represented byRon Coutts (Pioneer Road Services) andKevin McCullough (Boral).The Chairmanship transfers to AAPAthis year, with Kevin McCullough takingover chairmanship from Ian Reevesafter his two year stint. The board’saffairs are managed by three StrategicAlliance Managers - Queensland MainRoads Executive Director (Roads &Performance Delivery) Ross Guppy,Metropolitan District, ManagerAAPA Queensland Chairman, Kevin McCullough, Queensland Premier Anna Bligh andAAPA Qld’s Rob Vos at the Premier’s Annual Cabinet Christmas Reception in December2008.Program Delivery, Jenny McMillan andRob Vos, AAPA Queensland RegionalExecutive.PrinciplesGuiding principles of the strategicalliance agreement have been capturedin a commitment declaration andmanaged in the alliance framework ofwin-win or lose-lose with commitmentto foster innovation, and best outcomesthrough open and honest communications.Activities concentrate on three mainareas:• Better performing flexible pavements;• Responsive and viable road surfacingsector; and• Informed and well networked flexiblepavements sector.Communicating and deliveringthe goodsThe board operates with a formalbusiness plan which attempts tointegrate QDMR & AAPA goals withmedium term timeframe and is furtherguided by its five year strategic plan.The strategic plan was developed frominput received during inception of thealliance, is regularly updated, andprovides an integrating process for thedivergent wishes and needs of thesector. A copy of the plan is alsoavailable on the AAPA websitewww.aapa.asn.au under “QueenslandAlliance”.46 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWApart from the clearly definedprojects, the alliance promotes contactand communication across the roadsurfacing and flexible pavements sector.Newsletters are distributed on currentQueensland topics, updates released onprojects and a forum, or referencegroup, of key stakeholders isprogrammed for twice a year. Copies ofthe newsletters, and business plan,agreement, commitment sheet andreference group reports are available onthe web.Relationship buildingThe relationship building and informationsharing provided through thisprocess is valuable and has beenstrengthened in the process ofaddressing recent public criticism ofroad surfacing options and standards inuse in Queensland. Many will rememberthe local headlines and challenges whichhave been maturely reviewed and professionallyanswered through honest andopen sharing of information anddisclosure. The attitudes developedthrough the alliance operationspromoted and ensured this positive endresult.Through its regular meetings theReference Group plays an importantrole in sharing concerns and raisingissues for consideration by the boardalong with being the body that endorsesthe outcomes of projects and redirectsthem when necessary.Advantages brought by theStrategic AllianceOutgoing chairman of the Board, IanReeves, has summarized the advantagesas follows:• unique in the world, seniormanagement given full support;• moves beyond, and lifts above, thecurrent paradigm;• matches the need - improved responsibilitiesand commitment;• provides framework for findingsolutions together;• builds upon the good experiences ofthe liaison committees;• develops clear understanding ofcommon problems & issues;• leads to shared, improved outcomes,finding solutions together;• provides opportunities to innovate;• applies stretch goals & gets greaterinvolvement; and• greater opportunities - beneficialoutcomes to both partnersProjectsThe alliance has adopted an outcomesbased approach to addressing the issuesraised. This has resulted in formalproject management structures todeliver on a “time and managed resourcebasis” where Main Roads and AAPAspecialist teams are structured tooperate under higher level management.Work is signed off by the alliancemanagers and, through the approvedproject plans, the teams provide quickturn around and efficient solutions. Thisapproach has been honed over the yearssince 2001 with some of the projectsdelivering:Bitumen Sprayer CalibrationFacility at Nundah – the projectcovered the operations and basis of costrecovery, running of the facility to meetthe Austroads test methods and NATAaccreditation which included directinput and participation from state andnational offices of the association. Itsoperation is soon to be moved whichwill require ongoing participation.Asphalt Supplier RegistrationSystem – one of the most detailedregistration systems with the power tostop all asphalt purchases from adisqualified supplier. The registrationsystem applies to all asphalt supplied toMain Roads contracts and has ongoingreporting and auditing of projects andproduction. A first in this system is theclear statement of skills andcompetencies required frommanagement and field staff employedby the asphalt supplier. It is well linkedto national Vocational Education andTraining (VET) qualifications and hasattracted training support funding fromState and Federal Governments. The48 ROADS FEBRUARY/MARCH 2009

Rego System competency requirementhas contributed to the significant rolloutof training in Queensland againstthe Certificate III in BituminousSurfacings with some 50% of thepossible candidates (over 120 people)already qualified.SMA trials and specificationdevelopment – a project wasdeveloped to further enhance theperformance properties of the localStone Mastic Asphalt which includedoverseas status reports and, withsupport from AAPA National funding,the involvement of USA & EuropeanSMA experts. The revised specificationwas trialled on the Gateway Motorway,south east of Brisbane, where fourasphalt suppliers each laidapproximately one kilometre lengths ofthe surfacing. The works were fullyreviewed and learnings shared throughthe Austroads committees and havebeen included in the revised QDMRspecifications for SMA.Current projects - 2008 was a busyyear for alliance members, many of thesystems and projects were either wellestablished or close to implementation.Projects have been restricted to onesoffering early outcomes or highbenefits. They are:Sprayed Seal ContractorRegistration System – this will takethe concepts and learnings from theStone Mastic Asphalt being placed in Queensland.asphalts supplier systems into the allbituminous sprayed sealing acrossQueensland. Key aspects will be therequirement to use NATA certified andcalibrated bitumen sprayers, specifiedskills and competencies of contractorstaff including enhancedresponsibilities for quality andperformance of works. This system willdovetail with the planned Spray SealDesigner Registration system which isbeing developed through QDMR. It isexpected that the system will becomeoperational during the 2nd half of2009.Performance Based Specifications– arising from the desire to promoteinnovation, the project has undertakena review of the possible options and hasproposed the introduction of aQueensland based system to permitASPHALT REVIEWAsphalt Supplier Registration System project team – QDMR’s Barry Rule, Ian Reeves,Larry Mudge, AAPA’s Rob Vos and Trevor Parminter – Project Consultant.and encourage performance linkedalternatives to currently specifiedsurfacing and asphalt. This is beingbacked up through trials andassessment of proprietary products bythe Metropolitan Region.Surface Friction Characterisation –an increased focus on skid resistancehas identified the need for moredetailed understanding of the skidresistance performance of currentlyavailable products and materials.Sponsored by AAPA, this project isbeing undertaken by the QDMR RoadAsset Management Branch and seeks tocapture available skid resistance dataover time including measurementmethods with links to measurableproperties of the surfacing materials.National support has been includedand feedback will be provided throughnational and statecommittees.Technical SpecificationReviews – 2008 saw arewriting of all the QDMRbituminous productspecifications. From limitedto significant changes, thiswas handled through smallteams of experts in eachspecification field, whichincluded support on thebinders’ specifications fromnational binder suppliers.The changes will includethe allowance of RAP,greater attention (and sometrialling) of asphalt jointdensities, a project to assessthe point-of-use bandedvalues for PMBs andmovement towardsintroduction of aspects ofthe APRG 18 HMA designguidelines.ROADS FEBRUARY/MARCH 2009 49

ASPHALT REVIEWSPRAYED SEALINGPRACTICE IN AUSTRALIAThis is the second part of a paper presented by AAPA National Surfacing Engineer, Walter Holtrop,at the Sprayed seal Conference held in July 2008. It presents an overview of the Austroads SprayedSeal Design method to design the rates of application of binder and aggregate. The paper alsohighlights the essential information required and the attention to detail necessary to ensure anappropriate design. The third part of the paper will be included in the next edition of Asphalt Reviewand will provide information on Plant and Field Procedures required to produce a high and consistentstandard of sprayed seals.Sprayed sealsIntroductionThe following is an outline of thegeneral philosophy behind selecting aparticular type of sprayed treatment.The choice is influenced by theoperating environment, accepted andproven practice in the local area, availabilityof materials and whole of lifecost of the treatment.Generally, several treatments will besatisfactory and the designer will haveto make the final decision on choosingthe optimum treatment, taking intoaccount the above factors as well as therisk factor associated with eachtreatment for the prevailing conditionsexpected at the time of application. e.g.a PMB will be a very high risk treatmentin cold/damp weather conditions.The life of a sprayed seal is highlydependent on the quality of the granularbase materials and the standard ofsurface preparation of pavements priorto resealing.Main strengths of a seal are:• suitable for both initial and reseals• high flexibility• relatively low cost• high skid resistance (when applied toa uniform surface)• good waterproofing qualities• use of PMB and geotextiles for sealingand waterproofing existing crackedsurfaces• matches existing surface levelLimitations are:• will not strengthen a pavement• will not correct a pavement shape• high tyre noise, particularly withlarger aggregates• less satisfactory performance overnon-uniform or rutted surfaces• not suitable to treat intersections,roundabouts, heavy vehicle turningareas.ROADS AdvertisingTo reach the decision-makers in the roads field, you shouldconsider advertising in ROADS. For information on advertisingrates, please contact Yuri Mamistvalov at Hallmark Editions,Tel (03) 8534 5008 or email yuri@halledit.com.auEnvironmental considerationsThe first few hours in the life of a sealare critical with regard to performanceand any problems due to traffic orweather conditions. Therefore in theselection process due considerationmust be given to the risk of failure andlikely consequences for safety of thetraffic and potential environmentalpollution.Selection of aggregate sizeThe nominal size of aggregate chosenshould relate to the conditions for thejob and should be the best compromisefor the various conditions. The sandpatch test and surface texture allowancetable in the seal design method can beused as a guide to selecting aggregatesize for reseals taking into accountexisting texture. Table 5 sets out theaggregate sizes recommended based ontraffic volumes.Double/double sealsPreferred combinations are: 10/5 forfine texture as may be required inurban areas; 14/7 common for highspeed roads; 20/10 to provide a veryrobust seal, and 20/7 mm for robustseals requiring a smoother and finertextured surface.50 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWSAMGenerally as single/single sealsusing 10 and 14 mm only, because7 mm generally does not provide ahigh enough binder content to beeffective and economical. Adouble/double seal may be a 14/7,16/7, 20/10 or 20/7 mm combination.SAMIGenerally a single/single seal witheither 10 or 14 mm depending onthe rate of application of binderrequired for the conditions andtype and size of cracking, and typeand thickness of asphalt overlay.HSSSimilar to aggregates used innormal single/single ordouble/double seal.Spray generationLarger aggregates, with highertexture depths, generate less waterspray than fine aggregate seals onmedium to high speed roads.Noise considerationsSmall aggregates generate less tyrenoise than larger aggregates, andoften a double/double seal is used inurban areas to minimise trafficnoise.Surface texture requirementsMinimum surface texture toprovide skid resistance for highspeed rural roads is considered tobe about 1 – 1.2 mm as measured bythe sand patch test. Generally 10mm or larger aggregate is requiredon medium to high traffic volumeroads to provide adequate texture.Size 7 mm aggregate providesadequate texture on low trafficroads, or roads with speed limits of70 km/hour or less.Guide to selection of sealtreatmentsTable 6 has been developed toprovide a first step, quick andpractical guide to the selection of asuitable type of seal treatment forthe general conditions, andcommon performance requirementsspecified.ROADS FEBRUARY/MARCH 2009 51

ASPHALT REVIEWAustroads Seal Design MethodThe Austroads (2006a) seal designmethod (AP-T68/06) is the nationalmethod specified by all state roadauthorities. The development and use ofa practical, national design method isconsidered an important factor in thedevelopment and sustainability of theextensive national sealed road network.OverviewThe seal design is still loosely based onthe concepts developed by F M Hansonin the 1930s. Over the years the roadauthorities amended this design theoryto cope with changes in traffic volume,in particular the increase in heavyvehicles in later years, and in manyareas local factors were developed toachieve the desired outcome.In 1992, Austroads agreed to fundnational road trials to more accuratelypredict air voids in the compacted layerof aggregate in seals constructed withmodern equipment and subjected torolling by heavy vehicles, and inparticular large heavy vehicles.Road trials, covering many differenttypes of roads, traffic volumes andaggregates, were undertaken to moreaccurately predict the air voids in a sealconstructed with modern equipmentand subjected to rolling by currenttraffic, in particular by large heavyvehicles.The design procedure and informationprovided has been extended andimproved over the previous method;however there are several issues thatneed further investigation because oftheir influence on the outcome andperformance of sprayed seals.Monitoring of validation trials hasindicated that there are still severalaspects of the seal design method thatneed to be further improved, but thiswill require collecting further data.These aspects include matters such as:• Potential embedment of aggregate –how to measure this in a practicalmanner and determine practical ‘go –no go’ limits and appropriateallowances in the design processtaking into account traffic ranges,type of pavement, size of aggregateetc.• The effect of large heavy vehicles(seven or more axles) on therolling/packing of aggregate and voidsin the aggregate mat. This willdetermine the type and/or magnitudeFigure 10. Flow chart for design of binder application rates for a single/single seal.of adjustments that may be requiredto be made to minimise the potentialof flushing and loss of texture.Design procedureSprayed seals are a system, and sealingtrials and subsequent work have shownthat the design of the rates of applicationof binder and aggregate spreadrates are both of major importance inachieving a satisfactory performance forthe service conditions being considered.The design philosophy adoptedapplies principally to the design of themost common type of sprayed seal, thesingle/single seal using conventionalC170 bitumen as the binder and onesized 10 mm aggregate. Assumptionsincluded in the design of single/singleseals are:• Aggregate is single-sized and of appropriatequality. Average leastdimension (ALD) of the aggregate isan important input into the designmethod and must be representative ofthe aggregate being used. Theaggregate is expected to have between15 and 25% flaky particles (FI). If theFI is outside that range, anadjustment for aggregate shape has tobe made.• Design traffic volume is expressed invehicles/lane/day (v/l/d) and based onAADT, with between 5 and 15% heavyvehicles. If the heavy vehicles areoutside that range, an adjustment forheavy vehicles has to be made.• Aggregate spread rate determines theinter-aggregate void space in the seallayer, and hence the amount of binderrequired. A single layer of aggregateparticles settles with, typically,40–60% voids after orientation andpacking of the aggregate by rollingand trafficking.• Binder rise should be a minimum of35–40% up the height of the aggregateparticle after initial rolling andtrafficking, increasing to between50–65% (i.e.1/2–2/3) about two yearsafter construction.• The proportion of voids to be filledwith binder may be varied to optimiserequirements such as surface texture,52 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWmaximum seal life, and for specificapplications such as non-traffic areas.A minimum texture is generallyrequired for skid resistance.Design trafficDetermining the ‘Design Traffic’ is thefirst step in the design process. Thedesign traffic is expressed invehicles/lane/day (v/l/d) and is determinedfrom the AADT and calculatedseparately for each lane/area beingdesigned.Design of Rates of Application ofBinderA general schematic flow chart of theprocess for determination of binderapplication rates for single/single seals isshown in Figure 10.Basic Voids Factor (Vf)The Basic Voids Factor is an estimate ofthe voids in the aggregate after rollingand trafficking and is based on normaltraffic distribution and typical one-sizedaggregates used. The Basic Voids Factoris determined directly from a graph forthe design traffic. Refer to the centralblack line in Figure 11 which shows theBasic Voids Factor for design trafficbetween 50 and 500 v/l/d.For example, for design traffic of 400v/l/d, the Basic Voids Factor is 0.18L/m 2 /mm.Adjustments to the Basic VoidsFactorThere are two adjustments to the BasicVoids Factor to be considered in thedesign process.Adjustment for aggregate shapeFigure 11. Basic Voids Factor for 50 to 500v/l/d.Adjustment for effect of heavyvehiclesHeavy commercial type vehicles have alarge effect on aggregate packing andperformance of the seal, and inparticular the very large heavy vehicles(LHV), such as B Doubles, which aretrucks with 7 axles or more and grossmass exceeding 45 ton.A table is included in the designmethod for the “Adjustment to the BasicVoids Factor for Traffic Effects”Adjustment for heavy vehicles canvary the binder rate of application bybetween + 5% and as much as – 30%.It is estimated that Large HeavyVehicles (LHV) have a damaging effectabout three times larger than the normaltype of truck and trailer, or semi-trailer(HV). Using this concept, the effect ofheavy vehicles in the Adjustment isexpressed in “Equivalent HeavyVehicles” (EHV) and is determinedfrom: EHV = (HV x 1) + (LHV x 3).During the development of the designmethod various options were examinedto deal with heavy vehicles. The firstoption was to convert heavy vehicles tolight vehicles, but it was decided it wasimportant for the designer to separatelyconsider the effect of heavy vehicles inthe design process. A second option wasto use the Equivalent Standard Axles(ESA) concept as used in pavementdesign, but it was found this did notcorrelate well with seal performance.The concept of basing the design on atruck being the “standard vehicle” isbeing evaluated, with the effect of alltypes and classes of vehicle beingexpressed to that standard in terms ofeffect on a seal performance.A table is included in the Austroadsdesign method (AP-T68/06) for the‘Adjustment to Basic Voids Factor forAggregate Shape’ to easily determineany adjustment required.ROADS AdvertisingTo reach the decision-makers in the roads field, you shouldconsider advertising in ROADS. For information on advertisingrates, please contact Yuri Mamistvalov at Hallmark Editions,Tel (03) 8534 5008 or email yuri@halledit.com.auROADS FEBRUARY/MARCH 2009 53

ASPHALT REVIEWDesign Voids Factor (VF)(L/m 2 /mm)The Design Voids Factor is determinedfrom adding the Basic Voids Factorand Adjustments.The Basic Binder Rate ofApplication (Bb) L/m 2This Voids Factor is multiplied by theALD to calculate the Basic Binder Ratein L/m 2 .Bb = VF (L/m 2 /mm) x ALD (mm) L/m 2Allowances (L/m 2 )Allowances (in L/m 2 ) are made for thecondition and texture of the existingpavement surface.The allowances are in the same unitas the Basic Binder Rate and can beadded or deducted directly. Allowancesconsidered are as follows.Surface texture of the existing surface(most common allowance applied)This is measured using a standard testmethod (Sand Patch) and allowanceshave been developed to be appliedtaking into account the size ofaggregate in the existing seal, and thesize of aggregate in the proposed newseal. Typical allowances are + 0.1 L/m 2for a relatively smooth surface to +0.5L/m 2 for a coarse textured surfacewith, say, a texture greater than1.5mm.Embedment of aggregate into thepavement surface (initial treatmentsonly)A test method was developed for determiningpotential aggregateembedment. This is based on theNITTR method developed in SouthTable 7. Typical aggregate spread rates.Table 8. Typical polymer factors.Figure 5. Embedment hammer.Africa. A simpler and easier to usehammer has been developed and isbeing tried on a number of new worksto collect data and establish somepractical levels of embedment wheresome allowance has to be made. Risk isrelated to traffic volume and composition(in particular heavy vehicles) andthe aim is to initially establish some“go – no go” levels, and an indication ofthe allowance to be applied in the sealdesign.Typical values allowed forembedment are – 0.1 to - 0.3 L/m 2 .Embedment hammer is based on thestandard Marshall hammer used inasphalt mix design. Ball used is 19mmdiameter.Design Binder Rate (Bd) L/m 2The Design Binder Rate of Applicationis determined from the Basic BinderRate and Allowances as follows:Bd = Bb + Allowances (L/m 2 )Aggregate Spread Rates (ASR)m 2 /m 3Aggregate spread rates are considerablylighter than in previous designmethods. It is based on ALD, with someadjustments for traffic volumes,aggregate shape, type of binder andtype of treatment. For the mostcommon single/single seals the recommendedspread rates are determined asfollows:ASR = 850/ALD – 900/ALD (m 2 /m 3 )Based on average test results of ALDfor 7, 10 and 14mm typical spread ratesare:Design of Other SealsThe Basic Binder Rate (Bb) is determinedas for a normal single/single sealusing C170 binder. For other binders,such as PMB or emulsions, factorshave been developed to increase thebinder rate as appropriate. Forexample if the binder is a PMB theBasic Binder Rate Bb is multiplied bya Polymer Factor (PF) to determine themodified Basic Binder Rate (Bbm) asfollows:Bbm = Bb x PF (L/m 2 )Polymer factors have been developedfor the various treatments and type andclass of PMB used in the treatment.Table 10 provides an indication oftypical polymer factors used.54 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWGREEN ROADS ARE COOLROADS – WARM MIX ASPHALTThis paper is based on a presentation given at the 2008 Roading New Zealand Conference by DrBryan Pidwerbesky, Fulton Hogan General Manager Technical. It also follows an article in ContractorVol. 32 No. 8 September 2008 and is produced with the permission of that magazine.The adoption of the Kyotoprotocol and the rising cost of fuelis causing an ever increasing focuson greenhouse gas emissions andasphalt plant fuel usageworldwide. In response,technologies are now beingapplied that reduce the energyassociated with asphalt. Inparticular, these use a lowertemperature during bothproduction and placement, givingrise to a new class of asphaltmaterials called “warm asphaltmix (WMA)”.As those involved in the asphaltindustry will know, traditional warmmix asphalt is generally produced andplaced in a temperature range of around160 to 180°C to ensure the bitumen willcompletely cover the aggregate and thematerial can be effectively laid. Incontrast, WMA can be manufacturedand laid at significantly lower temperatures,from 110 to 140°C to achieve thesame bitumen coverage andcompaction.WMA requires less energy andtherefore reduces the greenhouse gasemissions associated with this stage ofthe road making process.WMA is being trialled around theworld including in New Zealand andAustralia. In New Zealand, FultonHogan General Manager Technical, DrBryan Pidwerbesky, gave a presentationto the Roading NZ conference late lastyear on cool asphalt and the advantagesit offers. He described WMA as havingthe basic characteristics as HMA interms of its spreadability, life anddurability. In fact in some instances, itappears to potentially have some advantages.Dr Pidwerbesky noted that there aretwo basic means of producing WMA,either by introducing an additive to themix or by foaming the bitumen usingwater. In both cases the aggregate canbe completely coated with bitumenensuring long lasting asphalt, but oneproduced at lower temperature.By reducing the energy required tomake bitumen the total greenhouseemissions are also reduced. This in turncan reduce the cost of asphaltproduction and transport.The lower temperature also allows forasphalt to be more readily transportedover large distances and there is also areduction of “blue smoke” during theloading and laying of asphalt.Other advantages of WMA includeimproved working conditions – saferworking environment due to lowertemperatures during production andplacement; reduced fumes andemissionsFrom a technical perspective WMAcan decrease binder ageing duringmanufacturing. It can also; allow forearly site opening; cool weather paving;extended construction season;compaction aid for stiff mixes; reducedoperation times in paving multiplelifts (i.e. less time to wait untilbottom layer cools down); lessplant wear – reduced degradationof drum and exhaust gasmanagement system; increasedplant production; longer storage;and retained workability of mixover longer haulage distances –due to lower limit in workabletemperature and slower temperaturereduction rate*.So, according to DrPidwerbesky, “The future of roadconstruction is not only greener, it’scooler too.”Dr Pidwerbesky also added that WMAis likely to be the standard asphalt in thenot too distant future. And it seems thatmany agree with him, with companiesin Australia and New Zealand gearingup to make warm asphalt.A WMA conference was held in the USduring November 2008. At thisconference, nearly 700 delegates wereadvised that WMA technologies promiseto reduce greenhouse gas emissions,conserve fuel, extend the paving season,and improve a number of aspects of theconstruction process.At the conference, Dale Rand of theTexas Department of Transportationdiscussed how his state would usearound 400,000 tons of warm-mixasphalt in 2008, and the prospect for2009 was that much more would beused. The conference was also told thatnumerous other US states were alsomoving in the direction of issuingpermissive specifications, which wouldallow contractors to use warm mix inplace of hot mix.More information about warm mix isavailable at www.warmmixasphalt.com,the official Web site of the Warm-MixAsphalt Technical Working Group. Thissite is managed by AAPA’s sister body –the US National Asphalt PavementAssociation (NAPA)ROADS FEBRUARY/MARCH 2009 55

ASPHALT REVIEWAs well as the rapid growth in interestin WMA in the US, there is also a rapidlygrowing interest in Europe with manyEuropean countries trialling andaccepting WMA.In New Zealand, Fulton Hogan andthe Christchurch City Council haveworked together to construct asphaltpavements using an advanced coolasphalt mix technology. Both organisationsare working to explore newinitiatives that result in road user safetyimprovements, community cost reductions,better asset performance fromlocal resources, longer asset lives andwider sustainability and environmentalimprovements.As a result, several sites have beenresurfaced with two of these sites beingheavily trafficked arterial roads inChristchurch. The trials are using virginaggregates but the company will nextlook at using RAP (recycled aggregateproducts).Dr Pidwerbesky says that researchand experience in the US and Europe,where large volumes of WMA havealready been laid, indicates that it is asgood as, if not better than, hotmix.In Australia, several companies havepurchased WMA plants and trials arebeing undertaken. In March of 2007,Citywide’s new North Melbourne plantproduced asphalt using a ShellBitumen Foam technology for a trial inKay Street, a residential street inCarlton, a suburb of Melbourne. Thetrial asphalt was produced at approximately125°C and paved below 100°C,resulting in an estimated reduction ofover 30% in greenhouse gas emissionsand energy consumption, up to a 50%reduction in fine dust and over 30%reduction in fume emissions duringproduction.After the work was completed RodMacBeth, Asphalt Operations Managerstated, “We were very pleased to see thatthe end product looked like hot mix –exactly as it should have!” He alsostated, “Just as importantly, our pavingcrew really benefited from the improvedworking conditions”.Other trials have been conductedaround Australia with a recent trial inBrisbane. The results of all these trialsin both Australia and New Zealand willbe closely monitored by all involved.Recent discussions between AAPAand the NSW RTA have resulted in bothorganisations agreeing to work togetherto trial WMA. The discussions recognisedthat industry and governmentmust work together if we are to reducegreenhouse emissions while continuingto provide high grade and long lastingpavement.The Austroads Pavement TechnologyReview Panel (PTRP) has also agreed tobring forward a project to help furtherevaluate WMA for Australia and NZ,although in NZ they are already movingquickly to apply WMA.The flexible pavement industry,including road authorities, must alwaysensure that pavements continue to meetour clients’ and the community’s needs.However, with increasing communityemphasis on greenhouse and environmentalissues, we must also constantlyseek means of reducing emissions andwaste.We already know that an asphalt orsprayed seal surface is significantly lessgreenhouse intensive that othermaterials such as concrete. However,governments and the community willcontinue to demand even loweremissions. Therefore, it is highly likelythat in the future that WMA will becomethe standard for road construction. Theflexible pavement industry mustcontinue to work together to ensure thatthe transition to WMA, combined withincreasing use of recycled asphalt, isdone responsibly and expediently forthe benefit of all participants, includingroad users.Contractor Vol.32 No.8 September2008. All articles on this website arecopyright to Contrafed Publishing Co.Ltd.WARNING ABOUT DODGY ASPHALT LAYERSAAPA and consumer affairs departmentsacross Australia have issuedwarnings about itinerant tradersoffering businesses and individualscheap and immediate sub-standardasphalt laying services.AAPA has posted a warning about thepractice on its website and the SAMinister for Consumer Affairs, GailGago, has issued a media statementalerting people to be on their guardagainst the scam.This follows similar warnings onmany government consumer websites.The websites also contain informationon identifying the people involved whomay offer cheap driveways, cheap roofrepairs or even cheap painting.AAPA has received reports of dodgyasphalt layers operating right acrossAustralia. These people offer quick,cheap asphalt, but demand immediatepayment and do not provide receipts orcontract documents. They usuallyclaim they have left over material fromanother job.Consumer affairs departments acrossAustralia warn that no matter howmuch pressure a trader puts on aperson, every offer of immediate workand immediate payment should berefused.Any person suspecting that theyare dealing with any of theseitinerant traders should not supplymaterial to them and should reportthe matter to the relevant stateconsumer affairs department. Asfurther information on these tradersbecomes available it will be includedon the AAPA website.56 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWAAPA TRAINING CENTRERELEASES TRAININGCALENDAR FOR 2009Training is a key to the success of anyorganisation.In the words of a senior humanresource manager in a major Australiancompany “The average company doesnot do enough training – that is whythey are average.”This applies to the flexible pavementindustry as well as every other industry.To continue to grow and prosper wemust all ensure that staff are appropriatelytrained. Alternatively our industrywill remain average or even fall wellbelow average. There is truth in thesaying that the most important asset ofany company is its staff.AAPA has a proud history of secondto-nonepractical and relevant trainingcourses for the flexible pavementindustry. And, as Louis Nucifora theAAPA Chairman advises in his column,the AAPA Board supports thecontinuous review of courses contentand of the range of courses beingoffered to ensure AAPA continues tomaintain the highest standard.Training is particularly necessaryacross the flexible pavement industry toensure that all staff can work safely andeffectively, achieving the increasinglyhigh standards that our clients and thecommunity demand from road surfaces.Some clients are also seeking evidencethat contractors’ staff are appropriatelytrained and qualified.With very mobile workforces commonamongst industries today, training is aneffective way to encourage good workersto stay in our industry. And of course,appropriately trained staff will workefficiently and effectively ensuring thatour industry is profitable and safe.Like many activities, laying a flexiblepavement looks easy to an outsider. Butthose involved in our industry know thatit takes significant skills and knowledge.AAPA Training has been offeringpractical and relevant industry-basedtraining for many years. AAPA Trainingis therefore a sure way of ensuring staffare effectively trained to work in ourimportant industry. All employers andemployees should review the trainingcourses being offered during 2009 andregister quickly to ensure a place.These courses cover all practicalaspects of pavement surfacing and if adifferent course is required, AAPATraining also offers a range ofcustomised courses addressing a widerange of topics. Additional courses andcustomised courses can also bedelivered in organisations’ ownworkplaces.To ensure the continued quality ofAAPA training, the Training Centre andcourses undergo regular internal andexternal quality assurance audits underthe ISO 9000 accreditation. Thisensures that course attendees receive a5-star quality delivery. AAPA Trainingis also a nationally Registered TrainingOrganisation (RTO) ensuring nationalrecognition of its training courses. Thisallows those who complete training toalso undertake an assessment towardsthe award of Certificate IV qualifications.AAPA Training also offers trainingmaterials at the certificate 3 level.These training modules are availablefrom AAPA Training and are designedfor in-house training in the followingareas:• Rake hand• Screed hand• Paver operator – Asphalt• Roller Operator – Asphalt• Safe use of SBS• Bitumen Spraying• Aggregate Spraying• Aggregate Rolling• Sweeping• Lowloader• Profiler• Aggregate Loading• Bitumen TankerAdded to these are a series of trainingresources developed under theCommonwealth Government’sWorkplace English Language andLiteracy (WELL) Program. These weredeveloped by AAPA and are available ina package comprising a CD-ROM andUser Guide to help those people in ourworkforce who don’t have English astheir first language or who may havesome literacy, or numeracy difficulties.These resources are:• Paving the Way ( a CD-ROM aimed atlaying asphalt)• Spraying Bitumen Successfully• Focus on Fire Safety• Working Safely with Hot BitumenA description of the major coursesoffered by AAPA is attached. Alsoattached is the calendar for 2009, butremember AAPA can also deliver thesecourses at your workplace and cancustomise courses to meet yourindividual needs.For all information please contactAAPA Training Centre on 03 9853 5322or email trainingcentre@aapa.asn.auROADS AdvertisingTo reach the decision-makers in the roads field, you shouldconsider advertising in ROADS. For information on advertisingrates, please contact Yuri Mamistvalov at Hallmark Editions,Tel (03) 8534 5008 or email yuri@halledit.com.auROADS FEBRUARY/MARCH 2009 57

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ASPHALT REVIEWAAPA TRAINING COURSES –TOPICS ON OFFERIn 2009, we again present a programfor all personnel involved in the flexiblepavements industry. These courses arerelevant to asset managers, engineers,technical officers, supervisors and keycrew personnel.Some courses are also relevant tonew entrants and those requiring arefresher. These courses are relevant toclients to help them better understandthe flexible pavement industry.AAPA courses:• are renowned for their relevance andexcellence• can be tailored to the needs of yourorganisation• are delivered by expert industrypractitionersThe suite of AAPA courses includes:Fundamentals of BituminousSurfacing“Learn about bituminous materialsand their applications.”This is a one day course that providesa comprehensive introduction tobituminous materials and their applicationin pavements. It particularlysuits the beginning of learning in thefield for new engineers, technical staffor construction personnel. It alsoprovides a valuable overview foremployees in administrative roles tohelp them better understand theindustry they are working in. Anyonebecoming involved in the flexiblepavement industry should do thiscourse.Bituminous Surfacing – Principlesand Practice“Learn how to design, construct andmaintain flexible pavements.”For managers, engineers and supervisorswith limited previous experiencein asphalt and bituminous materials,this three day course is renowned forproviding an invaluable coverage of thedesign, construction and maintenanceof flexible pavements, the manufacture,properties and safe handling of theconstituent materials and an overviewof plant operations. BituminousSurfacing – Principles and Practice isan ideal refresher course or to followon from the Fundamentals ofBituminous Surfacing. It is also anideal course for local government andother client groups as well as being anexcellent pathway to the greater depthof the more specialised courses.Courses are delivered in each stateusing a mixture of AAPA trainingpersonnel and local industry experts.Asphalt Placement & Compaction“Learn how to achieve a smoothriding surface – every time.”A one day course for engineers, supervisorsand key crew personnel in theprinciples and practices needed toachieve consistently high qualityasphalt work. Certificate IV compliant,it includes an overview of sampling andtesting, types of mixes, selection ofmaterials and quality control.Asphalt – Selection of PavementSurfacings“Learn how to select the best type ofsurfacing for each job.”This one day course goes to the use ofnational industry guidelines forselection of the most appropriate roadsurfacing for particular situations.Covering characteristics of varioustypes of surfacing, it will assist assetmanagers, engineers, technical officersand supervisors. It is Certificate IVcompliant.Pavement Maintenance Practices“Learn how to identify and repaircommon pavement defects.”A one day Certificate IV compliantcourse directed at all maintenancepersonnel, engineers and supervisors, itincludes the structure and function ofpavements, effective routine maintenancemethods to retain theirstructural integrity, discusses thematerials, plant and techniques usedand the fundamentals of assetmanagement systems. It concentrateson the practical aspects of sealedpavement maintenance and repairs andcontains practical and discussionsessions on material properties.PMBs & Bitumen Emulsions“Learn how to select PMBs andemulsions with confidence.”This specialised one day course on theselection and use of polymer modifiedbinders and bitumen emulsions coversthe range of such speciality products. Itis Certificate IV compliant, with thePMB section based on relevantAustroads technical reports.Working Safely with Bitumen“An essential safety training coursefor anyone who comes into contactwith bitumen.”Designed for all personnel engagedwith storage, handling, transport,working near or supervising the use ofhot bituminous products and asphalt.This course is also of value to officebasedpersonnel of the industry. Itconsists of formal presentations,practical exercises, graphic demonstrationsof potential hazards, class roomsessions and field training. The correctselection and use of fire extinguishersis included.Sprayed Sealing – Selection &Design“Learn how to select and designeffective spray seal treatments.”This two day course caters forengineers, supervisors and technicalofficers engaged in the supervision orsurveillance of sprayed sealing worksand the preparation of specificationsfor such contracts. Accordingly, it iswell suited to the needs of those in localgovernment and consultancy firms.The content is Certificate IV compliant.Sprayed Sealing – Design“Learn how to use the latest sealdesign methods with confidence.”The course meets the requirements ofpractitioners who, having attended theSelection & Design course in the past,wish to update their design skills inaccordance with the current Austroadsdesign method. It is offered either as astand alone one day course or as thesecond day of the Selection & Designcourse and is Certificate IV compliant.60 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWSprayed Sealing – FieldProcedures“Learn how to achieve high qualitysprayed work – every time.”A one day course, it is suitable forengineers, supervisors, key operatorsand can be readily modified to bepresented to all members of a sealingcrew. Participants learn the basicprinciples and field proceduresessential to consistently achievequality sealed work. It includes asession on calculations required forcorrectly determining materialquantities, sprayer adjustments andrates of application. It is CertificateIV compliant.“On the Job” TrainingSpecialised Course“Training targeted at peopleworking on equipment in the fieldThis is a customised sprayed sealingcourse held over 2 to 3 daysconsisting of short training sessionsfollowed by a specialist working withthe spraying crew to assess theirprocedures and standard of work. Itassists crews to work in accordancewith established/agreed benchmarks.The course concludes with adebriefing session to explain theassessment and discuss possiblemeans of improvement.Customised Courses“Contact AAPA Training to discussyour particular needs fortraining.”As well as the above courses, AAPAcan customise courses to meet yourparticular needs. These include areassuch as asphalt mix design andselection, asphalt specification andpavement rehabilitation andmanagement. AAPA also offers a“Nut and Bolts” course for peopleworking in the field such as localgovernment crews.Scheduled AAPA courses are listedon the AAPA calendar. However,these courses can also be delivered atyour workplace or a customisedcourse can be made to meet yourspecific needs.Call the AAPA Training Centre formore information on the currentlyscheduled courses or on customisedcourses, Telephone: (03) 9853 5322Facsimile: (03) 9853 5914, Email:trainingcentre@aapa.asn.au, Web:www.aapa.asn.auROADS FEBRUARY/MARCH 2009 61

ASPHALT REVIEWSAFE HANDLINGOF HOT BITUMENAAPA English Language and Literacy ResourceHot bitumen can be a dangerousmaterial if not handled correctly. It istherefore important that all workers inthe flexible pavement industry understandhow to work safely with bitumen.To assist workers who may have someEnglish language or learning difficulties,AAPA has prepared an inter-active CD-ROM and workbook on the safe handlingof hot bitumen. This resource wasdeveloped with funding from theCommonwealth Government under theWorkplace English Language andLiteracy Program.Health and safety is a major priorityfor everyone in our industry, indeed inany industry. However, not all peopleworking have English as their firstlanguage. There may also be otherAAPA currently has a range of AsphaltInstitutes publications available forpurchase. These include:AAPA PUBLICATIONSworkers with limited training in literacyor numeracy and others who may havesome learning difficulties. For thesepeople, warning signs and instructionsmay not be as clear as they are to thosewho have English as a first language.Companies must therefore use differentapproaches to training to ensure thatthese workers are able to handle bitumensafely.The Working Safely with Hot BitumenCD-ROM has been developed to assistthese workers. It contains a range oflanguage, literacy and numeracytutorials using written and spoken informationas well as video clips. There isalso an inbuilt database that recordsprogress and helps to identify gaps inlanguage and literacy skills enablingMS-4 The Asphalt HandbookThis is the Asphalt Institute’s comprehensivemanual on the use of asphalt.For 70 years it has served the asphaltindustry as a reference manual forcontractors, engineers, consultants anduser agencies. The new 700 page,expanded edition of text and illustrationsshowcases the advances in asphalttechnology with new topics including:• Superpave Asphalt Binder• Superpave Mix Design• Stane Matrix Asphalt• Open Graded Friction Courses• Quality Control Acceptance• Pavement Management• Rehabilitation of Concrete Pavementswith HMA.($160.00 + gst)MS-16 Asphalt in PavementMaintenanceProvides practical information onmethods, equipment and terminologyfor using asphalt to maintain all typesof pavements. Topics include maintenanceconsiderations, asphalt materialsused in pavement maintenance, descriptionsand causes of various distressesencountered in asphalt pavements, theproper maintenance procedures forrepairing pavement distresses andguidelines for designing stockpilepavement distresses. Numerous photosand drawings, with 80 pages. ($50.00 +gst)MS-22 HMA ConstructionThis manual provides critical informationon the basic principles andprocedures for constructing qualityasphalt pavements. The manualincludes chapters on Construction,Project Management, Quality Controland Acceptance of HMA, segregation,Materials, Mix Design, PlantOperations, Placement andCompaction. ($95 + gst)Other Publications available fromAAPAFor information about other publicationsavailable from AAPA refer to theAAPA website. Click on the link“Publications” to download the latestedition of the AAPA AsphaltPublications Catalogue.Note: AAPA members receive a members’discount for all publications availablefrom AAPA.trainers to clarify whether employeesneed to improve these skills in order towork safely and effectively on the job.This CD-ROM will not replace the needfor workers to receive appropriatetraining such as in the AAPA SafeHandling of Bitumen course orcompanies’ own in-house training. But itwill help workers to better understandthe issues associated with handling hotbitumen and to more effectively understandinstructions and messages.Working Safely with Hot Bitumen is thefourth training resource developed byAAPA under the WELL program. Theother three resources also provide basicinformation in clear and effective waysand are linked to the national CertificateIII – Bituminous Surfacing qualification.• Spraying Bitumen Successfully: Simpleand clear basic information to assist indeveloping communication and mathsskills required by a bitumen sprayeroperator.• Paving the Way: Simple and clear basicinformation to assist in developingcommunication and maths skillsrequired by an asphalt paver operator.• Focus on Fire Safety: Supports thedevelopment of language and literacyskills of employees working in asphaltand sprayed sealing operations.The information contained in theseresources may be of value to allemployees to refresh their knowledge inthese important areas of our business.Copies of the Safe Handling of HotBitumen training resource are being sentto the training sections of AAPAproducer member companies. Formembers who require additional copiesand for non-members, copies of any ofthe training resources may be obtainedfrom AAPA Training at a cost of $50(AAPA members) and $100 (nonmembers).An order form is attached.For more information refer to the AAPAwebsite (www.aapa.asn.au) or contactAAPA Training on (03) 9853 5322.62 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWNEW GENERATION BITUMENSPRAYERWhat do you get when you combine theexpertise of a leading tanker manufacturer,a civil road engineer, an exowner/contractor spray operator, and aroad sprayer maintenance engineer?The answer is one of the most technologicallyadvanced bitumen sprayersavailable on the world market.The `Easy Roader` bitumen sprayer isthe result of a partnership betweenTieman, a leading Australian tankermanufacturer and internationalcompany Specialised RoadingTechnologies. Although the partnershipis new between Tieman and SRT, thespraying technology has been in use,trouble free, for over eight years. It hasnow been developed into a bitumensprayer that has significant operatorand safety benefits.The right hand bar is set behind themain fixed bar. The left hand bar is setin front of the fixed centre bar. Thecomputer electronics time the switch onof all three bars independently so thebitumen hits the road from all threebars at exactly the same positionforming a straight line of spray.The sprayer is required to applybitumen to the road at the rates ofbetween 0.3 litres/sq.mtr and 3.0litres/sq.mtr in 0.05 increments to atolerance of plus or minus0.1litres/sq/mtr. It achieves this byprecisely controlling two things – thevolume of bitumen pumped through thejets and the speed at which the truck istravelling.When the application rate details areput into the computer by the driver, thecomputer gives the driver a smallnumber of transmission gear selectionoptions for road speed. After he hasselected what he considers to be theappropriate gear for the particularroad, the computer then automaticallysets the required engine speed andpump speed for the required applicationrate.When the run is completed, the spraybars lift up from the spraying heightposition back to their travel heightposition and the bars then retract tonormal width. The driver can obtain aprintout of all the consequential resultsof use. At the end of the day, all dataThe sprayer activation is electronicallycontrolled from the driver`s in-cabtouch screen computer. Beforeextension, the spray bars are lowered bythe computer from the travel heightposition to the spraying height position,set 250 mm from the ground. The spraybars then extend horizontally driven bythe hydraulic motor connected to thePTO at the rear of the engine anddirected by the computer in the cab. Asthe bars extend, the spray jets switch offand on automatically, and have a totalwidth of 6 meters.When the two moveable bars areretracted and a narrow strip is requiredto be sprayed, the driver can activateonly those jets required to achieve thatwidth. He does this from the cabthrough the computer.ROADS FEBRUARY/MARCH 2009 63

ASPHALT REVIEWreferring to the different jobs completedcan be downloaded to the companycomputer for recording, checking,invoicing and archiving.It is rare for the driver to have to leavehis cab with this new equipment but attimes he does, simply for a stretch. Hedoesn`t have the problems of dealingwith dirty, hot and smelly spray barsand he doesn`t have a mountain ofpaperwork to complete with the possibilityof mistakes through lost memoryor tiredness.Importantly, the design minimisesthe amount of time the operator spendsat the rear of the sprayer wherehandling hot spray bars and hot valvescan be risky with the danger of burns.The system also includes automatedsafety controls and interlocks to preventaccidents and damage to personnel orthe equipment.Cleaning of the spray jets is simplydone with a safe air purge system, notwith kerosene. The pump can then beflushed automatically with a minimalamount of kerosene re- entering thetank.Tieman has also integrated the SRTspray bar technology with its newgeneration stainless steel sprayer tank.The ringed construction guaranteesstructural integrity of the tank. Eachring is covered with a 25mm layer ofcork which ensures a 75mm air gap ismaintained for the Rockwoolinsulation. This unique design gives`best in industry` heat retention savingon re-heating costs both in gas andlabour. Of course not having future tankrust and corrosion issues due to thestainless steel, not mild steelconstruction, will significantly reducefuture maintenance and down timecosts.Tieman can offer an `Easy Roader`build time from placement of order inthe vicinity of four to five monthsdepending on truck availability.The `Easy Roader` sprayer is a safeinnovative solution for a roadconstruction industry that has seenlittle innovation in bitumen sprayers inmany years. The `Easy Roader`s ease ofuse will make it simple to train and keepsprayer operators working in the safestenvironment possible in an industrythat has always found it difficult to findexperienced bitumen sprayer operators.When companies invest for the future,the `Easy Roader` will be the preferredsprayer for spray operators in Australia.For further information,www.tieman.com.au or 03 9469 7600.VICTORIA PAVES A GREENFUTURE WITH LOW EMISSIONASPHALTOn 3 December 2007, Prime MinisterKevin Rudd announced Australia’sratification of the Kyoto protocol. Thefirst official act of the new LaborGovernment, it signalled a departurefrom the policies of John Howard.Mr Rudd returned from the UnitedNations Climate Change Conference inBali identifying the Garnaut ClimateChange Review as the premier guide tofurther action.The government’s response to thefinal Climate Change Report came withconditions, most aimed at giving itmaximum flexibility in global talksplanned for Copenhagen later this year.Although Ross Garnaut’s 10% emissioncuts were criticised by many greengroups, it put him at odds with theFederal Government which is anglingfor a minimum of 5% by 2020.The government hopes to introduce abill to parliament later this year with ascheme up and running in 2010. MrRudd also says the government will notignore the problems caused by climatechange while it deals with the globalfinancial crisis.“These are both real challengesresponsible governments can’t afford towalk away from either, you haveactually got to rise to the challenge, withboth I believe we have got the balanceright,” he said.Climate change is now coregovernment policy and Australia willhave a carbon emissions trading schemeand a tax on carbon emissions(currently estimated at $20-a-tonne).There will be a cost to pay for all,particularly energy intensive industriessuch a road building, and the consumeris highly unlikely to meet the fullexpense. Already under pressure, publicworks in both the private and publicsectors will be subject to rapid changein response to the imminent environmentalpolicy decisions of politicalleaders. The re-engineering ofAustralia’s physical services industry isvital to achieving national emissionstargets. However, with change comesopportunity and Citywide has been busypaving a greener path for Australia, oneroad at a time.In February 2008, Citywide openedthe doors of its high tech, redevelopedNorth Melbourne asphalt plant.Designed by world leaders, the SwissAmmann Group, it is the most environmentallysensitive asphalt facility in theSouthern Hemisphere.Reducing greenhouse gas emissionsby 30%, the plant incorporates cuttingedge pollution control, noise reductionand dust extraction technologies. Itproduces a suite of asphalt productswhich includes standard hot mix,Recycled Asphalt Product (RAP) andAustralia’s first low emission asphalt,Greenpave.Citywide Greenpave is made usingShell Bitumen technology tested onEuropean roads since 1995. Commonlyknown as warm asphalt mix or ‘WAM’ itis produced at significantly lowertemperatures than standard asphaltmixes. The new formula offers safetyand environmental benefits with performancestandards at or above thosepreviously available in the Australianmarket.Conventional hot mix asphaltproduction uses one grade of bitumenat approximately 170°C. In starkcontrast, Greenpave uses two binders ataround 110°C. Less susceptible toweather conditions, it offers greaterworkability and a longer construction64 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWseason. It is also subject to less oxidativebinder hardening, delivering betterfatigue performance over time and theoption of paving thicker layers. The newasphalt can improve productivity,reduce operational and repaving costs,and facilitate a rapid return to traffic.A reduction in production and pavingtemperatures of up to 60°C means asafer workplace and less carbonemissions. During application, CitywideGreenpave reduces employee exposureto heat and fumes and fewer emissionsare released in inner city communities.However, it is the environmentalbenefits that are really significant.Production and use of Greenpaveachieves:• a reduction in fume emissions ofmore than 30%;• a reduction in greenhouse gasses ofmore than 30%;• a reduction in fine dust of more than55%; and• energy savings of up to 30%.A growing number of Victoriancouncils are setting tough emissionstargets. In 2002, the City of Melbournelaunched its strategy, Zero NetEmissions by 2020 – A Roadmap to aClimate Neutral City. It not onlyrequires a 50% reduction in emissionsfrom city operations by 2010 but also a50% reduction in whole-of-municipalityemissions. The only way Melbournewill reach these targets is by influencingbusiness and residents while achievingreductions in every aspect of its ownbusiness.With road maintenance one of theprimary responsibilities of council,Melbourne was the first localgovernment to trial Greenpave on asuburban street in Carlton duringMarch 2008. After passing a trial periodit has now been laid at six sites acrossthe municipality. Former Lord Mayorof Melbourne, John So, led a councilwhich was strongly supportive of lowemission alternatives.“The use of Greenpave joins CH2 andthe Queen Vic Solar project as part ofthe city’s integrated strategy to reduceemissions. Citywide has shown howtechnology can be used to benefit theentire community,” he said.Melbourne’s new Lord Mayor, RobertDoyle, has indicated the environmentwill remain a top priority under hisleadership.In just 12 months, Greenpave hasbeen laid at 17 sites across metropolitanMelbourne. Seven councils (Melbourne,Boroondara, Wyndham, Moreland,Yarra, Manningham and Darebin) havechosen the new product, promoting itsuse through the local press and councilpublications. Community reaction hasbeen positive. The VictorianGovernment’s road authority, VicRoads,is also conducting a trial on the DeerPark bypass, due for completion laterthis year.Citywide Managing Director, KerryOsborne, says the early uptake ofGreenpave justifies the investment madein the North Melbourne plant.“We were confident communitydemand for environmental solutionswould drive local, state and federalgovernment policy. Now we have a fullyoperational plant and a proven productavailable to the Victorian market well inadvance of an emissions tradingscheme. As a result, Victorian councilsare one step ahead of the game.”Mr Osborne, an engineer, hasmarvelled at the change in communityperception towards his company’s civilcrews. “Despite being essential to citybasedtransport, asphalt has never beenthe most cherished of products. WithGreenpave, council works officers havefinally become the good guys,” he said.Citywide presented a 12-month reportcard at the 4th Australian RoadEngineering and Maintenanceconference on 17 February 2009 atAlbert Park in Melbourne.For more information on CitywideGreenpave call (03) 9261 5000.MAC – GREEN PLANTTECHNOLOGY AT ITS BESTMarini, a Fayat Group company, offersone of the world’s largest fleet of asphaltplants, with over 50 models available instationary, mobile or customisedversions.Marini asphalt plants have beenbuilding roads across the world for over100 years. The plants in Australia arethe benchmark for quality, productivityand profitability. These asphalt plantsare suited for a range of applicationsincluding production of low energyasphalts, recycled asphalt products,specification mixes or traditional hotmix asphalt.As we enter a new era of development,energy crisis andenvironmental concerns, Marinicontinues to foster its leadership roleby delivering products built tocustomers’ specifications, which providehigh quality results and unbeatablereliability. They also deliver reducedasphalt manufacturing costs – a must tosurvive in a competitive market – lowercarbon foot prints, reduced processwastes and minimal investments inproduct set ups. All these benefits provethe group’s commitment to sustainableand profitable development.Imagine, a full feature 320 Tphasphalt plant delivering consistentlyfour tonnes of mix every 45 seconds.The plant itself does not require civilfoundations, with each componentdesigned as a self-standing unit. It doesnot have ducts to fit, occupies minimalspace and is dimensioned for ease intransport and erection. That’s exactlywhat engineers at Marini had beingpursuing, which led to the design of theMarini Asphalt Compact or MAC, as itis now popularly known.This product incorporates the designhighlights of the world renownedULTIMAP series and green planttechnology at an affordable price.ROADS FEBRUARY/MARCH 2009 65

ASPHALT REVIEWMAC is available in two standardsizes, MAC 200 and MAC 320, delivering200 and 320 tonnes per hour. MAC canbe configured with various standardoptions that are available.Green plant technologyLarge capacity plants which normallyare destined to work almost round theclock inevitably have to be designedwith energy saving features, a conceptwhich runs through each level ofcomponent design in the MAC. Thestrategic placement of bag house filteratop the dryer drum offers substantialfuel savings by heat recovery, shortercircuits for gas and reclaimed filler. Asthe world gears up to make greenerroads, MAC series of asphalt plants aregreen technology ready.Environmentally readyInsulated critical components,negatively pressurised tower components– along with a highly efficientdual stage pollution control unit – meetstringent environmental emission andnoise directives with margins largeenough to meet future norms. Theplant can be configured to operate on awide range of environmentally safefuels.Lower maintenanceAdvanced material science technology,a reduced number of components andthe latest generation power transmissiontechnology add greaterreliability and lower the need forattention and maintenance.Profits – each time you relocateThe self-standing plant design negatesthe use of any civil foundation andensures your profits each time yourelocate. The deftly dimensioned subassembliesreduce transportation costsand ensure faster and easier site set ups.Modular plant design with pre-wiredcomponents further magnifies MAC’sgreen plant technology, by reducingoperating hours of cranes and othermaterial handling devices.Safety and serviceThe MAC incorporates modern plantsafety and process interlocks. All criticalprocesses in the plant are constantlymonitored and verified by the PLC.Large access, ergonomically designedgalvanised platforms, railings,walkways and guards are supplied as astandard to ensure years of uninterruptedservice, even in severe operatingconditions and under productiondemands. Conformance to special safetyneeds or country specific norms isoffered on request.Service and trainingMarini offers 100 % Australian serviceand support to all its clients through itslocal partner Paving Plant andProcesses. Various levels of trainingprograms are in the offing for fieldprofessionals.Future readyThe plant can be configured to meet anykind of mix demands for production oflow energy asphalts, High content RAP,traditional mixes, fibre/ colour additionetc. Various options like specialisedmixing for low energy asphalt, RAPproduction, long duration storagesolutions, solutions in bitumen heatingand storage, weighing and docketingetc. are available.MAC incorporates designs that willmake your business and investmentsfuture ready, all the while ensuring yourproductivity, performance and profits.For details on Fayat’s complete productrange including mobile and stationaryplants available in continuous or batchmixing technologies please contactBlesson Varghese – Area Sales Manager(Australasia), on +91 9925 007371 ormail to blesson@marini.fayat.comFor all your road needs, goto www.roadsonline.com.auNEW APPOINTMENTSSTRENGTHEN ASPHALTBUSINESSConplant’s asphalt plant business,Conplant Bitumen Equipment (CBE), isfocusing on growing market share inAustralia, with two major new appointmentsrecently announced.Conplant Managing Director, IanColeman, says the new appointmentswill bring an additional layer ofexpertise to the business, andstrengthen support for customersAustralia wide.“I am very pleased to announce theappointment of Maryam Zoljalali andPaul Vandersluis to the positions ofGeneral Manager and Technical SalesManager respectively. I know they willadd a new dynamic to the business andwill assist us in taking CBE to the nextlevel,” Mr Coleman says.CBE was established a year ago whenConplant purchased Auckland-basedBitumen Equipment as part of itsstrategy to expand its asphalt plant salesand extend its support capabilities andcapacities. CBE now offers sales andinstallation of Ammann asphalt plantsin addition to manufacturingcontinuous type plants (parallel flowand twin drum) and upgrading existingplants.“We’ve recently installed an AmmannWAM warm-mix foamed bitumensystem, which is delivering significantenvironmental benefits to ourcustomers. Warm mix asphalt reducesthe temperature required forproduction. This process uses less fossilfuel and results in lower emissions,” MrColeman says.Maryam and Paul joined CBE earlythis year, and their skills willcomplement the expertise of TechnicalSales Director, Brian Atkinson. Brianfounded Bitumen Equipment approximately20 years ago and has beeninvolved in the industry for over 30years.“The new appointments will help usto grow Conplant by bringing the corebusiness areas of Conplant AmmannAustralia closer together, capitalising onthe knowledge, skill-sets, resources andgeographical spread of the whole organisationto best serve our customers.“Maryam’s role will be based out ofAuckland and Sydney, so she’ll haveclose contact with Conplant’s Sydneymanagement team as well as the CBE66 ROADS FEBRUARY/MARCH 2009

ASPHALT REVIEWteam in New Zealand. Maryam has aMasters of Electrical Engineering andbrings with her a broad range ofexperience gained from a diverse rangeof industries including IT, telecommunications,finance and transportation.“Paul Vandersluis has been withConplant since 2006 as Branch andClient Services Manager – SunshineCoast. During his time in the role thebranch has seen considerable successand growth and the wealth ofknowledge he gained in this previousrole will be invaluable for CBE.”Mr Coleman says Conplant iscommitted to its asphalt business,which it sees as a natural extension ofits existing business focus.“As the Australian distributor ofAmmann compaction equipment andthe nation’s leading compaction salesand hire business, Conplant sees itsasphalt plant business as an exceptionalfit. Our new appointments demonstratethat we’re serious about continuing toprovide an exceptional level of serviceand expertise to asphalt customersthroughout the Australia, New Zealandand Pacific Island region.”For further information, visitwww.conplant.com.auNEW TANDEM ASPHALTROLLERS FROM DYNAPACDynapac brings two new asphaltcompaction rollers to Australia. Thenew Dynapac CC224HF and DynapacCC424HF rollers are designed toachieve quality asphalt finish, efficiencyin operation and ease of service.The CC224HF for the 7-8t and theCC424HF for the 10t class are designedto meet the needs of road contractors,contractors and rental companiesworldwide.According to John Davison – NationalSales and Marketing Manager, DynapacAustralia – the new rollers have beendesigned to achieve high quality surfacefinishes offering operational featuressuch as ‘soft’ starting and stopping toprevent bowing or cracking in theasphalt layers.“The smooth starting and stoppingfeature, also known as Electronic DriveControl, is an Australian first and allowseven unskilled roller operators to startand stop without leaving marks,” hesaid.As a safety feature, the machine willdrop out of the ‘soft’ mode and brakeimmediately if the lever is movedquickly, signalling the need for anemergency stop.Mr Davison also says the otherAustralian first is the central watertank with a 900L capacity.“The tank’s location gives the operatorclass-leading vision and optional extrafront and rear water tanks giving a totalwater capacity of 1,400L, reducingdowntime,” he said.New features simplify and speedservicing to guarantee maximum availability.Use of a double pump vibrationsystem, for example, eliminates theneed for a vibration valve, making thesystem more efficient, aiding servicingand reducing fuel consumption.The Dynapac CC224 is powered by aCummins QSB 3.3 T3 water-cooledturbo engine with after cooler and ratedat 60 kW (80 hp) at 2200 rpm and is alsoavailable with a 74 kW (99 hp) engine.The Dynapac CC424 is powered by aCummins QSB 4.5 water-cooled turbodieselengine with after cooler and israted at 82 kW or 93 kW at 2200 rpm.Dynapac’s automatic engine idlingsystem cuts the idling speed after 10seconds at full rpm in neutral. Thisfurther reduces emissions, providesadditional fuel savings and minimisesnoise.Operator efficiencyHigh quality compaction is enhanced byoptimising the ergonomics, ensuringthat operators have continuous visibilityof the operation and easy access to thecontrols. The machines feature 1x1 mvisibility and full view over drumsurfaces, drum edge and sprinklernozzles.The clear control panels on the newDynapac models provide operators theinformation they need. All the gaugesare displayed – water, fuel, voltage andnumber of hours – and the operator canchange between menus at the touch ofa button. With the engine relocated onthe rear module, noise levels arereduced for the operator and engineheat is removed from the operator’splatform. It also gives easy serviceabilitywith both engine and hydraulicsfully reachable through the large hoods.Many of the enhancements bringenvironmental benefits through reducedconsumption or quieter operation.Efficiency enhancements have savedsome 8 kW in the operation with consequentimprovements in the runningcost and noise.Compaction ControlThe optional Dynapac CompactionAnalyzer for Asphalt (DCA-A) providesaccurate time information about therolling, allowing the next pass to beplanned, taking into account the asphalttemperature of each area. Tracking thenumber of passes makes it easy for theoperator to maintain control of thepattern and achieve the best results.Better planning of the rolling operationalso ensures jobs are carried out moreefficiently, resulting in using less fuel.Further information can be providedthrough the optional DynapacCompaction Analyzer software, whichindicates the temperature in front ofand behind the roller as well as thenumber of passes made on each sectionof the asphalt, for optimumcompaction.For further details please contact: JohnDavison at Dynapac on 02 8868 9700 oremail: john.davison@dynapac.comROADS FEBRUARY/MARCH 2009 67