刚性桩复合地基变形特性离散元分析  

DEM Analysis of Deformation Behaviour of Rigid Pile Composite Foundation

作　　者：董友扣[1] 郑俊杰[1] 潘玉涛[1] 

机构地区：[1]华中科技大学土木工程与力学学院,湖北武汉430074

出　　处：《土木工程与管理学报》2011年第4期12-15,共4页Journal of Civil Engineering and Management

基　　金：国家自然科学基金(50908112);教育部留学回国人员科研启动基金(20091341);华中科技大学研究生科技创新基金(HF-08-01-2011-240)

摘　　要：采用离散元法(DEM)软件PFC2D模拟了刚性桩复合地基单桩模型试验,避免了之前广泛采用的有限元法(FEM)、有限差分法(FDM)等连续体法在模拟刚性桩复合地基褥垫层时的不足,并基于离散元模型对刚性桩复合地基中桩体刺入量及地基的水平位移、竖向位移等变形特性进行了分析。分析结果表明:在桩顶处1/4椭圆形的区域内褥垫层颗粒的沉降明显小于其他区域内颗粒的沉降;水平位移主要集中在基础下的三角形区域内,褥垫层颗粒在发生水平位移时受到了桩体的剪切作用;桩体在影响褥垫层颗粒竖向位移方面主要起阻挡作用,而在影响褥垫层颗粒水平位移方面主要起剪切作用。This paper establishes Discrete Element Method （DEM） model of single-pile model test of Rigid Pile Composite Foundation （RPCF） with software PFC2D, which avoids the deficiency of the widely-used continuum methods such as Finite Element Method （FEM） and Finite Difference Method （FDM）） in simulation of sand cushion in RPCF. Based on the DEM model, the deformation behaviour of RPCF, including penetration of pile and horizontal and vertical displacement, is analyzed in this paper. The results show that, the settlement of the particles in the quarter of ellipse zone above the pile head is significantly less than its counterparts of the particles in other zones~ The horizontal displacement mainly occurs in the triangle zone under the footing and cushion particles are sheared by the pile. The rigid pile hinders the cushion with the cushion settling vertically, while the pile shears the cushion with its moving horizontally.

关 键 词：离散元法 刚性桩复合地基 褥垫层 桩刺入 颗粒流 

分 类 号：TU473.1[建筑科学—结构工程]