桩-土-承台相互作用的有限元简化模型

针对低桩承台结构计算中往往只考虑桩土作用,忽视承台与土相互作用的问题,通过工程实例,建立考虑桩-土-承台相互作用的低桩承台有限元简化模型,分析桩间土的承载作用对承台和桩内力的影响。结果表明:在简化模型中考虑桩间土的承载作用后,承台弯矩和桩基轴力可减少35%～40%;桩身弯矩和剪力主要受水平力和土体m值影响;桩基轴力随地基土基床系数的增大而逐渐减小,但减幅逐渐趋缓。

Simplified finite element model of pile-soil-base slab interaction

In low pile platform structure calculation,the pile-soil interaction is usually only considered without the base slab-soil interaction.Based on engineering practice,we establish the simplified finite element model for low-pile-platform structure to analyze the influence of internal force of base slab and pile when the bearing capacity of soil between piles is considered.The results show that the moment of base slab and axial force of pile can be reduced by 35%~40% if load-bearing capacity of soil between piles is considered in the simplified model,while the bending moment and shear force of pile foundation are determined by horizontal force and soil m value.The axial force of pile decreases with the increase of soil bedding coefficient,but the damping gradually decreases.