Normalization method for asphalt mixture fatigue equation under different loading frequencies
来源期刊:中南大学学报(英文版)2015年第7期
论文作者:Lü Song-tao ZHENG Jian-long
文章页码:2761 - 2767
Key words:road engineering; asphalt pavement; fatigue equation; loading speed; loading frequency; strength; stress ratio
Abstract: In order to analyze the effect of different loading frequencies on the fatigue performance for asphalt mixture, the changing law of asphalt mixture strengths with loading speed was revealed by strength tests under different loading speeds. Fatigue equations of asphalt mixtures based on the nominal stress ratio and real stress ratio were established using fatigue tests under different loading frequencies. It was revealed that the strength of the asphalt mixture is affected by the loading speed greatly. It was also discovered that the fatigue equation based on the nominal stress ratio will change with the change of the fatigue loading speed. There is no uniqueness. But the fatigue equation based on the real stress ratio doesn’t change with the loading frequency. It has the uniqueness. The results indicate the fatigue equation based on the real stress ratio can realize the normalization of the asphalt mixture fatigue equation under different loading frequencies. It can greatly benefit the analysis of the fatigue characteristics under different vehicle speeds for asphalt pavement.
Lü Song-tao(吕松涛), ZHENG Jian-long(郑健龙)
(National Engineering Laboratory of Highway Maintenance Technology,
Key Laboratory of Highway Engineering (Ministry of Education), School of Traffic and
Transportation Engineering, Changsha University of Science and Technology, Changsha 410114, China)
Abstract:In order to analyze the effect of different loading frequencies on the fatigue performance for asphalt mixture, the changing law of asphalt mixture strengths with loading speed was revealed by strength tests under different loading speeds. Fatigue equations of asphalt mixtures based on the nominal stress ratio and real stress ratio were established using fatigue tests under different loading frequencies. It was revealed that the strength of the asphalt mixture is affected by the loading speed greatly. It was also discovered that the fatigue equation based on the nominal stress ratio will change with the change of the fatigue loading speed. There is no uniqueness. But the fatigue equation based on the real stress ratio doesn’t change with the loading frequency. It has the uniqueness. The results indicate the fatigue equation based on the real stress ratio can realize the normalization of the asphalt mixture fatigue equation under different loading frequencies. It can greatly benefit the analysis of the fatigue characteristics under different vehicle speeds for asphalt pavement.
Key words:road engineering; asphalt pavement; fatigue equation; loading speed; loading frequency; strength; stress ratio