Three-dimensional finite element analysis of the seismic behavior of inclined micropiles

This paper presents a thorough study of the behavior of inclined micropiles under seismic loading. Analysis is carried out using a full three-dimensional finite element modeling. The soil media is assumed to be elastic with Rayleigh damping, while micropiles are modeled as 3D elastic beam elements. The structure is described by a single degree of freedom system composed of a concentrated mass and a column. The paper is composed of four parts. The first part includes a literature survey on the behavior of inclined micropiles. The second part presents the numerical model used in this study. The third part concerns analysis related to the influence of micropiles inclination on the seismic behavior of a group of micropiles embedded in a homogeneous soil with a uniform stiffness. The last part deals with the seismic behavior of inclined micropiles embedded in a soil layer with a depth-based increasing stiffness. The results of this study provide valuable information about the influence of micropiles inclination on dynamic amplification and on the seismic-induced internal forces in micropiles. (C) 2004 Elsevier Ltd. All rights reserved.