Frame Shear Wall Structure-Pile Raft Foundation-Soil Interaction Analysis

In this paper, I established the three-dimensional numerical finite element model offrame shear wall structure-piled raft foundation-soil interaction based on ANSYSfinite element software, and consider the foundation soil elastoplastic constitutiverelation, analyzes different foundation soil deformation modulus, different pile length,different pile spacing, and different pile diameter, different raft thickness andconstruction process of the interaction effect. Due to the differential settlement causesthe upper structure to produce larger stress, so the article will anlysis the interactionfrom the angle of base settlement and upper structure internal force.I established the finite element model of upper structure-pile raft foundation-soilinteraction based on ANSYS finite element software, Set surface contact elements toconsider the contact friction between the pile and soil, Consider D-P criterion is used asa foundation soil constitutive relationship.Through numerical simulation, this paper get the main achievements include:①The foundation modulus, pile length, pile spacing, and pile diameter, raftthickness of the pile raft foundation settlement, the differential settlement are there existcertain degree of influence. Among them the pile length is the most important influencefactors of base settlement; Raft thickness of base settlement has a significant effect onthe differential settlement. When the design to appropriately increase the pile length canbe a very good control base settlement and differential settlement, when the foundationsoil is more homogeneous, the effect of control the differential settlement is notapparent only through increase the pile length, should be appropriately increased raftthickness. At the same time, uneven pile not well controlled basis of differentialsettlement, should consider the pile raft foundation leveling design variable stiffness.②Consider the interaction, the upper structure stiffness contribution is limited.Consider the interaction, the upper structure internal forces and conventional designmethod of the internal force redistribution of the get the difference is larger, can appearside pillar of the column load, reducing load, and shear wall will be part of the columnconnected to share the load of shear wall, in practical projects should be caused takeseriously. At the sametime, when the foundation longitudinal relative bending0.35‰~0.75‰between C and D shaft axis appear the maximum bending moment of the girderends the increase of the phenomenon. These changes are as basis of the reduction of longitudinal bending relative decrease.③Uniform cloth pile case, reduce the basis of differential settlement in the upperstructure of the secondary stress angle starting for the existence of the upper part of theshear wall structure, basic longitudinal relative bend should be less than0.5‰.④From the point of controling base differential settlement, through thedimensional analysis got the pile raft foundation raft thickness formula, for preliminaryestimates raft thickness has certain directive significance.