摘要
邻近斜坡沉桩问题近年来在工程实践中经常遇到,由此引发的工程事故时有发生。由于沉桩边界条件的非轴对称特性,理论分析方法精确求解会遇到较多困难。本文采用离散单元法二维颗粒流程序(PFC2D),克服传统的连续介质力学模型的宏观连续性假设,研究沉桩过程中斜坡土体的挤土位移场变化规律。结果表明:随着桩体的不断沉入,斜坡挤土位移影响范围越来越大,斜坡土体的位移模式也不断发生变化;紧邻桩身以及靠近桩端范围内的土体,在桩体径向挤压以及桩侧摩擦的共同作用下,产生了向下的位移,而桩身一定距离以外的土体,受地表及倾斜自由边界的影响,表现为竖向隆起位移;当沉桩至斜坡底面以下深度时,后续沉桩对斜坡的挤土位移影响不大。
In recently years, the problem of pile sinking adjacent to slope often happen in the practice and initiates many engineering accidents. Due to the non-axisymmetric characteristics of pile sinking boundary conditions, it is difficult to solve this problem by theoretical solution. The paper used the two - dimensional particle flow code （PFC2D） of discrete element method to analyze the slope squeezing dis- placement under pile sinking adjacent to slope in the process of pile sinking, which can overcome the macroscopic continuity hypothesis of traditional continuum mechanics model. The results show that the in- fluence scope of slope squeezing displacement is more and more larger with the constantly pile sinking, and the squeezing displacement mode of slope also gradually changes; soil adjacent to the pile body and pile terminals produces downward displacement under the combined action of radial extrusion of pile and its side friction, the squeezing displacement of the soil in a certain distance away from the pile body pro- duces vertical uplift displacements under the influence of soil surface and inclined free boundary; the subsequent pile sinking has little influences on slope squeezing displacement when the pile sink to the ar- ea below the slope bottom.
出处
《水资源与水工程学报》
2013年第4期1-5,共5页
Journal of Water Resources and Water Engineering
基金
国家自然科学基金青年基金(51208301)
国家自然科学基金项目(41272288)
上海高校青年教师培养资助计划项目(slg12019)
关键词
邻近斜坡
沉桩
挤土效应
颗粒流
adjacent to slope
sinking pile
soil squeezing effect
particle flow code
