Indoor Test Research on Fatigue Performance of Cement-stabilized Macadam

摘要

Indoor test research is performed for fatigue performance of cement-stabilized macadam of four mix proportions by adopting cylinder specimens shaped by vibration compaction method. Four mix proportions are respectively 3% and 4% cement dosage with gradation as framework-dense structure and suspend-dense structure. Weibull distribution is applied to establish fatigue equations of cement-stabilized macadam. With the fatigue equations, the tensile strength structural coefficient is established, which is used in the tensile stress check for cementstabilized macadam as base of asphalt pavement. The result indicates that fatigue performance of cementstabilized macadam with framework-dense structure gradation surpasses that of suspend-dense structure gradation when cement dosage is quite low. Along with increase of cement dosage, gradation influence on fatigue performance is not large;while cement dosage influence is quite evident on fatigue performance. The higher cement dosage has better fatigue resistance. The numeric scope of the fatigue equation regression coefficient a of cement-stabilized macadam under 50% failure probability is 1.1035~1.1345, and b is 0.0413 ~0.0454. The fatigue performance of cementstabilized macadam is not below concrete material at all. The outcome can be used for reference in tensile strength structural coefficient in material design and structure design.