Bearing Capacity and Settlement of Vertically-Loaded Piles: Fid-Bau Portal

Bearing Capacity and Settlement of Vertically-Loaded Piles

Škrabl, Stanislav

This paper presents both treatment of the bearing capacity of and estimated settlements for vertically-loaded piles in an elasto-plastic foundation ground. The solution presented is based on an elasto-plastic analysis of the interaction between bored reinforced piles and a non-linear foundation ground. Both the piles and the foundation ground are analyzed using the finite element method. In the latter case, an elasto-plastic constitutive model for dry soil conditions is also considered. Based on the results of analytical solutions and numerical analyses, a generalized model for interaction analysis between elastic piles and an elasto-plastic foundation ground has been made. The significance of the proposed generalized model is reflected above all in the fact that more accurate predictions of vertically-loaded piles' bearing capacity and deformations with different ground characteristics and geometrical data are made possible, based on a limited number of non-linear analysis results. The results of some parametrical analyses concerning the most important impact factors are also presented. The results of the research are presented in the form of diagrams which, for the selected ground characteristics, including the relative stiffness of the piles and the ground, as well as actual geometrical data, enable us to make more precise simultaneous predictions of the piles' bearing capacity and displacement. The capacity of individual piles is expressed as the dependency of allowable displacements, the shear strength and deformability of the ground, the relative stiffness of the pile and the ground, and the diameter and depth of bored piles. The second part of the paper presents a comparison between the results of non-linear interaction analyses and the results of field static tests. The conclusions provide indications as to the application of the research results in geo-technical practice. The results of the research are presented in the form of diagrams, which are very simple to use in geo-technical practice.