Application of Dynamic Stability Criterion in Evaluating Field Rutting of Asphalt Pavements Using the Wheel Tracking Test

Abstract

In this study, the application of the dynamic stability (DS) criterion to evaluate rutting of asphalt pavements using the wheel tracking test is presented considering field pavement conditions. A simplified model estimating the rut depth of asphalt pavements was first developed considering the DS, the number of load cycles (N), the maximum shear stress (τmax), and load duration (t). To develop the model, indirect tensile (IDT) and uniaxial compressive strength (UCS) tests were conducted to measure cohesion (c) and internal friction angle (ϕ) of three asphalt mixtures. In addition, seven types of asphalt mixtures were evaluated to determine their DS using the wheel tracking test. To determine the average maximum shear stress, a predictive regression equation was established through the KENLAYER program with various combinations of asphalt concrete (AC) modulus, subbase and subgrade resilient moduli, and layer thicknesses. Based on the rutting performance of six pavement sections from the WesTrack test, the rutting model was validated and applied to different AC layer scenarios. It was found that the proposed model is accurate in estimating the rut depth of AC layers under varying load and environmental field conditions. Application of the DS criterion in evaluating rut depth for asphalt concrete is proposed using the developed rutting model.