Fatigue Life Prediction of High Modulus Asphalt Concrete Based on the Local Stress-Strain Method

• Published in: Applied sciences Vol. 7; no. 3; p. 305
• Main Authors: Zheng, Mulian, Li, Peng, Yang, Jiangang, Li, Hongyin, Qiu, Yangyang, Zhang, Zhengliang
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.03.2017
• Subjects: Asphalt; Asphalt pavements; Concrete; Crack initiation; Crack propagation; Fatigue life; Fatigue tests; Finite element method; Fracture mechanics; high modulus asphalt concrete; Life prediction; local stress-strain; Materials fatigue; Mathematical models; Metal fatigue; modified Neuber equation; pavement engineering; Pavement overlays; Prediction models; Stress-strain relationships; Tension; True stress
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app7030305

Previously published studies have proposed fatigue life prediction models for dense graded asphalt pavement based on flexural fatigue test. This study focused on the fatigue life prediction of High Modulus Asphalt Concrete (HMAC) pavement using the local strain-stress method and direct tension fatigue test. First, the direct tension fatigue test at various strain levels was conducted on HMAC prism samples cut from plate specimens. Afterwards, their true stress-strain loop curves were obtained and modified to develop the strain-fatigue life equation. Then the nominal strain of HMAC course determined using finite element method was converted into local strain using the Neuber method. Finally, based on the established fatigue equation and converted local strain, a method to predict the pavement fatigue crack initiation life was proposed and the fatigue life of a typical HMAC overlay pavement which runs a risk of bottom-up cracking was predicted and validated. Results show that the proposed method was able to produce satisfactory crack initiation life.