Master's Dissertation
DOI
10.11606/D.18.2010.tde-10032010-104324
Document
Author
Full name
Wagner Queiroz Silva
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Carlos, 2010
Supervisor
Committee
Coda, Humberto Breves (President)
Komatsu, José Sergio
Paiva, João Batista de
Title in Portuguese
Análise não linear geométrica do acoplamento solo-estrutura através da combinação MEC-MEF
Keywords in Portuguese
Acoplamento MEC/MEF
Interação solo-estrutura
MEC
MEF
Abstract in Portuguese
Title in English
Non linear geometric analysis of soil-structure interaction via BEM/FEM coupling
Keywords in English
BEM
BEM/FEM coupling
FEM
Non linear geometric
Soil-structure interaction
Abstract in English
This work presents an alternative coupling of the boundary element method (BEM) and the finite element method (FEM) to create a computer program for non linear geometric analysis of frames coupled to continuous domains, applied to soil-structure interaction. A linear elastic behavior is considered for the soil, modeled by BEM. An alternative formulation is adopted for the classic sub-region technique, allowing the consideration of multiple inclusions and load lines inside the soil domain. The BEM computational code is coupled to the AcadFrame software, based on positional FEM for non linear geometric analysis of frames, considering exact kinematics. The numerical coupling is made by an algebraic formulation where the soil stiffness matrix and contact forces are condensed and added to the structure matrix and internal forces for each iteration on Newton-Raphson process. On both programs it is adopted a generalization of the element degree assuming the Lagrange polynomials, which allows the use of curved high order elements. It was also implemented the least square method in order to obtains better and smoother results of surface forces in the contact interface. The obtained results are satisfactory and prove the formulation efficiency. The program allows the analysis of buildings supported by layered soils with multiples inclusions and load lines. It considers directly supported elements over the soil (footing foundations, radies) and internal elements in any direction, like vertical and diagonal piles. It can also consider piles going through different layers of the soil. This formulation can be applied to other elastic problems like coupling between mechanic pieces and composite material analysis.