Finite Element Analysis Applied To Interaction Of Soil-Piled Raft Foundation-Superstructure Of Shear Wall

With the rapid development of the skyscraper in recent years, the research on theory and application of superstructure-foundation-soil interaction has become a heated topic gradually. Many of previous researches considering interaction were mainly centered around frame structures, subsoil of soft soil, but documents of the superstructure with a pure shear wall and loess as the subsoil are very few thus far. Accordingly, this article took an actual engineering as example, in the light of some problems existing in interaction-considering studies and actual situations of shear-wall structures and foundations, established a reasonable FEA model by the use of FEA software SAP2000 and conventional software for structural analysis and design. Through FEA, the influences due to interaction of shear-wall structure-piled raft foundation-soil on internal forces and deformations were investigated, and the main research work is as follows:(1) In detail introduced the present status of research and application with shearwall structure-piled raft foundation-soil interaction considered, accentuated the load-bearing characteristics and research methods of piled raft foundations, and addressed problems required to be studied in this article.(2) Analyzed the definition, essence, analytical principle and mechanism of interaction, emphatically compared research methods of interaction and several foundation models frequently utilized.(3) Employed two kinds of software: PKPM, SAP2000, established a FEA model without considering the interaction; profoundly discussed the delimitation of artificial borders during modeling, interception of subsoil range, selection of elements, etc.(4) In accordance with calculation results by two models described above, compared differences and superiorities between both software, and the applicability of SAP2000 for national codes in our country.(5) By the software SAP2000, performed a finite element analysis with the interaction considered or not for the same engineering example; explored the influencing law of interaction on internal forces and deformations of superstructures, and proposed corresponding design suggestions.(6) On the basis of the analytical model considering interaction, changed such parameters as rigidity of superstructures, thickness of raft, pile diameter, rigidity of subsoil etc., systematically researched the interaction among shear wall structure-piled raft foundation-soil, and put forward the structures and geological conditions in which the interaction should be taken into consideration, which will provide references for a reasonable design of shear-wall structures.