Programming for finite element analysis for transient elasto-plasticity in concrete using 3D brick element - step by step procedure
Keywords:
FEM; Elasto-plasticity; 3D-brick element; Drucker-Prager; yield criterion.Abstract
Finite Element Method (FEM) of analysis is a very powerful computational tool. The objective of the paper is to summarize the theory and the associated programming algorithms developed for a 3 dimensional, 8 noded brick element employing isoparametric formulation. The dynamic elasto-plastic analysis is required for analysis of special problems in civil engineering like analyzing the effects of collision due to a vehicle or an errant ship on bridge structure, application of a moving force like wheels of a loaded truck moving on the deck. A set of connected subroutines were developed to investigate concrete bridge piers subjected to collision loads. The developed subroutines can also be employed to investigate the elasto-plasticity induced in concrete subjected to any dynamic load, with a few modifications as required by the user. The programs are validated using ANSYS software with acceptable difference in the results. An attempt is made to document a systematic algorithm of the programs developed to solve the problem of material non-linearity in concrete coupled with dynamic analysis using a three dimensional element.