Discrete Cohesive Zone Model And Its Application

For many other engineering materials, such as high-grade pipeline steel, braidedcanbon fiber composites, concrete, rubber, nonlinear effect of crack tip is similar to thelinear material in the presence of a blunt crack tip. Traditional fracture parameters hardlycharacterize the fracture properties of the materials. In order to solve such problems, theconcept of cohesion zone was introduced in this paper instead of the fracture process zonein the crack propagation process and discrete cohesive zone model (DCZM) to simulatefracture initiation and subsequent growth.Firstly, DCZM model proposed by Xie was modified, and fracture interface elementwas developed using the modified DCZM model. Reasonableness, accuracy andinsensitivity on the grid of the modified fracture interface element were verified. Forsubsequent analysis of high-grade pipeline steel, braided canbon fiber composites,concrete, rubber materials laid a foundation.Two parameters (fracture energy and cohesive strength)of the cohesive zone modelwere obtained through experiments, and the compact specimen based on the DCZM modelwas used to conduct the numerical simulation research to the high-grade pipeline steel(X80and X70); The quasi-brittle materials such as concrete and asphalt concrete wereequivalent to elastic material, and single edge notched beam and simplied wedge samplewere used separately for the fracture properties of asphalt concrete and concrete materialbased on DCZM model; subsequently the DCZM model was used for the preliminarystudy on fracture properties of the braided canbon fiber composites and rubber material.Parts of the results of the numerical simulation results are good consistent withexperimental results and the numerical simulation in references.This fracture interface element, instead of compliant layer in continuous cohesiveelement, with easy convergence, insensitive to mesh and computational efficiencyadvances, can be used for the analysis of fracture properties of metals, quasi-brittlematerials and other materials.