Analysis of Isolated Battered Pile and Soil Interaction via BEM/FEM Coupling

Resumo

The use of battered piles is more and more recurrent in view of their efficiency in certain problems,
these are deep-foundation elements widely used in civil engineering due to their ability to reach more resistant soil
layers and to support large loads. Bearing in mind that the numerical analyzes appear as an alternative in relation
to the empirical analyzes, the present work aims to perform the numerical analysis of isolated battered piles and
in groups through the BEM/FEM coupling. The pile is modeled by several finite elements of three-dimensional
frame with two nodes, five nodal parameters and any inclination. The soil is modeled by the boundary element
method, being considered a semi-infinite, elastic-linear, homogeneous and isotropic medium. Having been the
fundamental solution of Mindlin used, the soil discretization is done only on the contact surface with the pile, it is
not necessary to discretize the soil surface. The coupling of the BEM / FEM formulation is done considering the
transformation of the matrix of soil coefficients (BEM) into a matrix equivalent to the FEM, which added to the
stiffness matrix of the three-dimensional frame provides the final system. The interaction forces at the stake-ground
interface have a linear distribution. The results obtained were validated by comparison with those available in the
literature, showing effectiveness and robustness of the formulation. Finally, the results of which showed little
influence of the angle of inclination on the displacements of isolated battered piles.