挤密桩应力的弹塑性理论及有限元分析

Elastic-Plastic Theoretical and Finite Element Analysis of Compaction Pile Stress

本文基于统一强度理论分析挤密桩桩周土体应力,得出挤压力与塑性挤密半径关系式,并推导出挤密桩桩周土体达到极限状态时的挤压力极限值表达式,分析了极限值随各参数的变化规律。然后,基于大型有限元分析软件ANSYS8.0对挤密桩挤密成孔过程进行三维有限元模拟,通过非线性计算得出各种情况下的极限荷载与理论分析结果进行对照分析。经比较,证明基于统一强度理论的分析结果更符合土体实际受力状态,与三维有限元分析结果更接近。结果对于全面研究挤密桩的综合作用效用有一定的参考价值。

This paper studies the soil stress between compaction pile based on the Unified Strength Theory. The relationship of the extrusion pressure and plastic compaction radius has been deduced. Obtains the expression of limit bearing capacity as the soil between compaction pile being extruded. Analyses the limit bearing capacity regularity as the parameters change. Then does three-dimensional finite element simulation of compaction pile during the hole formation based on the large finite element analysis software ANSYS 8.0. Through nonlinear computation, gets the limit load in every case that compared with the theoretical ones. Through comparison illustrates that the analysis of soil stress between compaction piles based on the Unified Strength Theory is more agree with the actual soil stress and the three-dimensional finite element analysis result. The obtained results have practical value for comprehensively study the function of the compaction pile.