Effect of Stress Levels and Temperatures on Creep Compliance of Asphalt Binders

Abstract

Abstract: Mostly, the laboratories in Pakistan use DSR (Dynamic Shear Rheometer) Test AASHTO T 315 for quality control purposes but it was designed for unmodified asphalt binders, and it gives inadequate results of modified binders. On the other hand, AASHTO T 350 called as multiple stress creep recovery (MSCR) test gives better result for modified binders. MSCR grades of mostly modified binders with additives, nano composites, viscous fluids is determined in this research paper. The effect of these modified as well as unmodified binders on the Creep Compliance factor is also evaluated. To characterize Creep Compliance factor along with Stress Sensitivity and Traffic Loading this test is now used. For evaluating the Stress Sensitivity of modified binders there is development of new factor called as JNR Slope instead of JNR Difference. Jnr Slope gives vast representation of asphalt binders and there is no congestion left between them. The binders which fail in JNR Difference might get satisfactory results from JNR Slope Which gives better results than the conventional way of testing. For determining the rutting behavior of modified as well as unmodified asphalt binders there is usage of peak strain factor at stress level of 100 Pascal, and 3200Pascal relatively. The values of JNR at the stress levels 25 Pascal to 25600 Pascal gives almost linear variation between modified as well as unmodified binders. This research paper is developed to determine Peak strain values, Creep Compliance factors, Stress Sensitivity Factors, And MSCR grading according to the Traffic Loading.