结合上海软土地区的某一实际桩基工程,根据土层实际分布和基桩试验结果,使用颗粒流方法研究了成层土中的桩-土相互作用.对于单根桩,采用平行黏结模型来表征不同土层与单桩的相互作用,使用现场静载试验所得荷载位移关系曲线来标定平行黏结模型中的细观力学性质参数,建立了考虑土层成层分布和试桩结果的桩土相互作用颗粒流模型,得到了该桩对应不同土层的桩-土相互作用细观力学性质参数;对于全部试桩亦同法处理,得到了不同试桩对应土层的细观力学性质参数;结果表明,使用颗粒流方法可以较好模拟桩与成层土的相互作用;由宏观参数确定细观参数的多元线性回归方程时,个别相关系数小于0.5、大多数大于0.5、部分达到了0.9以上;由细观参数确定宏观参数的多元线性回归方程时,个别相关系数小于0.6、大多数大于0.8,拟合效果较好.%Based on a real pile foundation project in the soft soil ground in Shanghai,the interaction between pile and layered soils was investigated using the particle flow method considering the layered soils and pile test results.For a single pile,after considering the real distributions of soil layers and the load-displacement curves obtained in field,the parallel bonded models were established,with the calibration of the mechanical parameters in a meso-scale based on in-situ load-displacement curves.The parallel bonded models of other insitu test piles were then established using the same method,and the corresponding meso-parameters were thereafter obtained.The results show that the particle flow code method can effectively simulate the interaction between the piles and layered soils.In determining the mesoscopic parameters from the macroscopic ones,few of the correlation coefficients in the equations were less than 0.5,most of the coefficients were greater than 0.5,and a part of the coefficients reached 0.9 or more.In the equations obtained from the mesoscopic parameters to the macroscopic ones,a few of the correlation coefficients in the equations were less than 0.6,the rest of the coefficients were greater than 0.8,indicating that the regression result is relatively reasonable.
展开▼
