Research On The Fatigue Performance Of Cement Stabilized Subbase Course Materials

Semi-rigid asphalt pavement is primary structural style of pavement in my country, and the durability of semi-rigid base affects the usage and durability of asphalt pavement. However, the design value of compressive resilience modulus is the initial value, which is tested in steady state and indoor. The design value doesn't consider the modulus deterioration of semi-rigid base materials in the real stress state. So based on the fatigue test, the paper develops a research on the modulus deterioration of semi-rigid base materials under dynamic loading, and on the fatigue performance of semi-rigid base materials.Firstly, the paper selects of cement stabilized crushed rock including suspend-dense structure, framework-dense structure and task force graduation, and the first two structural types are presented by the pavement design specification. Then the paper comparatively analyzes the strength index and the stiffness index of different molding methods. Through the analysis, the compressive strength is no coherence with the splitting strength and the flexural-tensile strength. In view of its strength index and well usage in practical engineering, the task force graduation is selected to study the fatigue performance and modulus deterioration laws of cement stabilized crushed rock. Secondly, through comparing the indoor methods of fatigue test, the paper determines the splitting fatigue test for the main method. The fatigue equation is theoretically revised, and compares the fatigue equation abroad and home. In the test process, compression resilience modulus is tested after a certain cyclic loading, on the basis of test, modulus deterioration laws after the dynamic loads of cement stabilized crushed rock is studied, and the modulus ratio of different decay stage of compression resilience modulus is presented. meanwhile, the effective value of periodic modulus is determined by means of the initial modulus of basement course.