Asphalt Review - Volume 29 Number 2 (June / July 2010)

ASPHALT REVIEW
a range of different WMA materials.
The asphalt companies also agreed to
fund the initial and ongoing extensive
asphalt testing that was required under
the Evaluation Protocol. The testing will
be monitored by state road authority and
ARRB personnel.
To ensure consistency in placement
reduce costs and enhance practicality,
one company undertook all the
placement. This highlighted the high
level of cooperation between all the
parties involved in this major project. It
also ensured consistency in the laying of
the samples and meant that all sections
could be laid over three nights, reducing
disruption to traffic.
The Project required placing 21
different WMA and hot mix wearing
course sections of asphalt in a grid
pattern on the section of the roadway
and this was undertaken in April 2010.
Two foamed WMA processes and two
additive WMA processes were used to
produce the WMA materials. Some WMA
materials were made with new aggregates
and others with differing proportions of
reclaimed asphalt pavement (RAP), from
10% up to 50% RAP.
Testing of the asphalt materials used
could not be completed by a single
laboratory given the large number of
samples.
As a result, each participating asphalt
company prepared the specimens and
completed testing for their own mixes.
Representatives from Queensland
Transport and Main Roads, NSW Roads
and Traffic Authority, South Australian
Department of Transport Energy and
Infrastructure, VicRoads and ARRB
were present during the preparation
of samples and during the asphalt
placement.
The asphalt specimens are currently
being tested by the asphalt companies
with state road authority and ARRB
observers monitoring that testing. The
observers will continue to monitor
all testing undertaken throughout
this project to ensure accuracy and
consistency.
As outlined in the Validation Project
Protocol, this project will continue
for a period of at least two summers.
During that time, industry, ARRB and
state road authority members will
continue to monitor the performance
of the pavements. This will provide
a clear understanding of the relative
performance of WMA to hot mix.
It is expected the outcomes of the
validation project will confirm that
WMA, with or without RAP, is as reliable
as hot mix. But whatever the outcome,
this project will enable both government
and industry to better understand
the opportunities to use WMA across
Australia. It will also help to achieve
greater consistency in specifications
across Australia and will support the early
use of WMA with all its environmental,
economic and safety benefits.
The project highlights the benefits
of industry and Austroads/state road
authorities working together through
AAPA to achieve outcomes that benefit
all parties. It not only reduces the costs
to any single organisation, it significantly
reduces the need for duplication.
Importantly, the project also highlights
how government and industry can work
effectively together through AAPA.
This is highlighted in a letter from
Andrew Milazzo, Executive Director of
the SA Department for Transport, Energy
and Infrastructure, sent to the AAPA
CEO, John Lambert, about the project:
“The Department is delighted to be
involved in a project such as this which
encompasses the State Government’s
strategic goals of attaining sustainability
through greenhouse gas emissions
reduction and improving wellbeing
through greater safety at work.
I appreciate the co-operative approach
you have taken with the free flow
of information, showing a genuine
commitment from industry.” Further
information on this project will be
made available on the AAPA website
and in future editions of Asphalt Review.
Information can also be obtained from
the joint project managers, Cassandra
Simpson (AAPA) and Kieran Sharp
(ARRB).
20 ROADS JUNE 2010/JULY 2010