中文摘要：

分别采用室内模型试验与颗粒流数值模拟的方法,对砂土中受水平荷载的桩顶自由短桩桩周土体在加载过程中的应力和位移的发展变化规律以及桩土相互作用性状进行了较系统和深入的研究。在室内模型试验中,研究了短桩在松砂、中密砂、密砂中的位移荷载规律,桩前、桩后土压力的分布和发展规律;并重点通过数字图像无标点量测技术密切关注桩周土体的位移产生和发展变化过程。通过开发颗粒流程序模拟室内模型试验在加载过程中的桩土相互作用过程中应力和位移的发展变化规律,与模型试验的结果进行了对比。给出了砂土中受水平荷载的桩顶自由短桩较完整的变形和破坏模式及极限土压力分布形式。

英文摘要：

The model tests and PFC^2D （Particle Flow Code in 2 Dimensions） numerical simulation method were applied to investigate stress and displacement of the soil around the horizontally loaded free-head short piles in sand during loading. Aimed at samples of loose, medium and dense sand, advanced digital photographic non-target method was adopted in the test to identify the digital images of the model, and to measure the change of displacement of piles and soil around them under loading The soil pressure on lateral side of the piles, load and displacement of pile head was measured in model tests. The stress and displacement of the soil around the piles was simulated by PFC^2D and compared with the results from the model tests. By analyzing the load-displacement relation of pile head, position change of piles under pile load, soil pressure distribution on the piles and its variation with load and displacement ＇of pile head and development of stress in the soil around the piles, a deformation and failure mode of free short piles in sand under horizontal load and distribution mode of the critical earth pressure were obtained.