Updating Bituminous Stabilized Materials Guidelines Mix Design Report Phase II

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gives a quality specimen, which in turn produce a reliable result. Figure J.14 is a photo of final cut of BSM-emulsion of Quartzites with no active filler. 2.3 MMLS3 Testing Two sets of similar mixes were prepared for the MMLS3 testing. One set tested in the wet condition and another in dry condition. After MMLS testing, the ITS test is done to enable determination of the tensile retained strength (TRS), i.e. wet over dry ITS. The initial MMLS3 tests carried out on four different BSMs. Two BSM-emulsions and one BSMfoam was tested after accelerated laboratory curing, and one BSM-emulsion tested after curing in the laboratory at room temperature for more than 9 months. In addition, four more BSMemulsion mixes tested as indicated in Table J.1 above. The steel beam set-up accommodates nine briquettes of which seven specimens are monitored during trafficking; the other two are placed at either ends of the traffic path as dummy specimens. The dummy specimens are made of HMA, which does not fail under the dynamic effects of the wheel loads during the transition onto the trafficked specimens. The layout of the briquettes and the profilometer guide indicated in Figure J.15. Dummy 07 06 Profilometer guide 05 04 03 02 01 Steel beam Dummy Figure J.15: The layout of the briquette and profilometer guide The layout of the seven monitored specimens may include different combinations. Two different combinations are appropriate in one test for statistical purposes. The combination may monitor three briquettes of either BSM-emulsion and/or four of BSM-foam, made of different aggregates type or with and without active filler. The profile of the trafficked briquettes measured using a profilometer at exponential intervals of trafficking. All the briquettes measured except the dummy specimens at the ends of the beam. After every interval, i.e. a defined number of load repetitions, the MMLS3 is removed from the set-up and the profile of the surface of the briquettes measured. 12
The set-up of the test before trafficking commences, is a time consuming procedure. After the specimens fastened into the steel beam, water is filled to a level in the bath 2mm above the specimen’s surface. The water depth is kept steady by a weir at the end of the bath. The water is pumped out of the weir and repeats the cycle all the time to maintain water level. The water temperature during testing maintained at 25ºC using a thermally adjustable water pump. The number of load repetitions at which profile measurements are taken differs according to the type of BSM. Generally, more measurements are made early on during the test i.e. at shorter intervals, because the rutting profile has an exponential relationship with time. However, as shown in the following table, the number of load repetitions at which the MMLS3 test is terminated, can vary significantly: Table J.2: The number of load repetitions per measurement cycle wet condition BSM Type Loads per measurement cycle [No] Initial (preliminary ) test 2% emulsion +1% cement DNM 50 000 75 000 100 000 (long cured) 2% emulsion + 0% cement (G2) 0 500 900 Failure 2% emulsion + 1% cement (G2) 0 250 Failure - 2% foam + 0% cement (G2) 0 250 Failure - Additional test 2% emulsion +1% cement (H-RAP) 0 45000 Failure 2% emulsion +1% lime (H-RAP) 0 45000 Failure 2% emulsion +0% cement (H-RAP) 0 2500 Failure 2% emulsion +0% cement (Q-G4) 0 2500 Failure Failure = means ravelling –depth more than 12mm After identification of the number of wet-trafficked axles to failure for a specific mix, the second set of briquettes tested under dry condition to the same number of load application applied for wet condition. Thereafter two sets specimens (dry and wet) could be tested in the ITS mode to determine the tensile strength retained TSR i.e. wet over dry. 2.4 ITS Testing Subsequent to trafficking, Indirect Tensile Strength (ITS) tests carried out on the specimens removed from the MMLS3 test set-up. These tests results were then compared with ITS tests performed on specimens not subjected to wet trafficking. In this way, a TSR result assessed for the different BSM-mixes. The Indirect Tensile Strength test performed using MTS equipment. The loading rate applied during ITS test is 50.8mm/min. The Indirect Tensile Strength and tensile strength ratio of the BSMs computed as follows, Equation 1 and 2: 13
Page 1 and 2: APPENDIX J Technical Memorandum Upd
Page 3 and 4: findings of the moisture damage tha
Page 5 and 6: Figure J.4: The measuring wheel of
Page 7 and 8: An electric calibration unit used t
Page 9 and 10: 2.2 BSMs for MMLS3 testing The inte
Page 11: Figure J.12: The side view of the b
Page 15 and 16: 3. TEST RESULTS The use of vinite o
Page 17 and 18: Table J.7: ITS results after wet an
Page 19 and 20: Table 11: Ravelling-depth after MML
Page 21 and 22: Table 15: Tensile Strength Retained
Page 23 and 24: The comparison of BSMs on Figure J.
Page 25 and 26: From Figure J.19 it can be seen tha
Page 27 and 28: 4.3 Saturation Level The moisture i
Page 29 and 30: Ravelling-Depth [mm 16 14 12 10 8 6
Page 31 and 32: From the study conducted in MIST de
Page 33 and 34: - No sign of significant initial de
Page 35: 5. BIBLIOGRAPHY ASPHALT ACADEMY. 20

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