关键词: 循环荷载, 模型试验, 桩顶累积沉降, 单桩

Abstract: Traffic loads will affect the performance of the pile foundation underneath the expressway and high-speed railway. To analyze the influence of cyclic loads on the settlement of the pile foundation, laboratory model tests are used to study the effects of the cyclic number of loads, the cyclic load ratio (CLR), the static deflection load ratio (SLR) on the pile head cumulative settlement of the single pile in the double-layer foundations. The results show that the pile head cumulative settlement of the single pile under cyclic loads is obviously affected by the number of cycles, SLR and CLR. The pile head cumulative settlement increases with the number of cycles, CLR and SLR. The pile head cumulative settlement development under cyclic loads has the trend of increasing rapidly first and then slowly. If the values of the SLR and the CLR are small, the pile head accumulated settlement in the later stage increases very slowly or not. If the values of SLR and CLR are large, the pile head accumulated settlement increases faster in the later stage. When the value of SLR + CLR is constant, the more the proportion of the CLR is, the larger the pile head cumulative settlement is. The effects of the CLR and the SLR should be considered in the engineering design. 

Key words: Cyclic Loads, Model Tests, Pile Head Cumulative Settlement, Single Pile