Evaluation of Recovered Fracture Strength after Light-Healing of Graphite-Modified Asphalt Mixtures with Integrated Computational-Experimental Approach

摘要

This paper presents an integrated computational-experimental approach for evaluating recovered fracture strength after light-healing of graphite-modified asphalt mixture beams. The cyclic fracture and light-healing tests were conducted to measure the recovered fracture strength of the asphalt mixture samples as reported in another paper. A two-dimensional (2D) multiphase bilinear cohesive zone model (CZM) was employed to predict the original and recovered fracture strength of the asphalt mixture samples. The digital image correlation (DIC) method was used to analyze the crack displacement variation of the samples during the fracture and light-healing processes. The relative strain ratio from DIC, originally measured fracture energy, and peak separation stress were combined to calibrate the recovered fracture energy of beams after light-healing processes. Two input parameters, calibrated fracture energy and peak separation stress, were used to simulate the sample fracture behavior and predict the recovered fracture strength. The relative difference of the fracture strength between the simulation and experiments was calculated to validate the 2D bilinear CZM simulation. The results indicated that the CZM with calibrated fracture energy and measured peak stress is capable of predicting the recovered fracture strength after fracture and light-healing cycles.