Gravity model testing overconsolidated soft clay under repeated moving loads
WANG Jia-chao1, 2, QIAN Jian-gu1, 2, ZHANG Jia-feng3, WANG Qi-wei1, 2
1. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China; 2. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University, Shanghai 200092, China; 3. Shanghai CAAC New Era Airport Design & Research Institute Co., Ltd., Shanghai 200335, China;
Abstract：A gravity model test device is developed to simulate overconsolidated soft clay under repeated moving loads. Using this device, the model tests on Shanghai shallow overconsolidated saturated soft clay are carried out. Through a series of tests, it is revealed that temporal and spatial variation of the accumulated pore pressure and deformation about overconsolidated saturated soft clay foundation with the number and amplitude of changing repeated moving loads. The test results show that the dynamic response of the excess pore pressure in the deep soil is obviously lower than that of shallow soil, but its peak value comes earlier. At the same time, the dynamic response of soil in the direction of moving loads is stronger than that in other directions, and the dissipation of the excess pore pressure in that direction is also the least obvious. In addition, with the amplitude of increasing dynamic loads, the plastic deformation at the initial stage and the displacement increment at the later stage get larger, and the difference of settlements at different horizontal positions becomes larger too.
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