Smoothed floating node method for modelling cohesive fracture in quasi-brittle materials

Abstract

This paper presents a numerical framework for implementation of cohesive zone model with smoothed floating node method (SFNM) for failure analysis of quasi-brittle materials. The nonlinear behavior of material inside the fracture process zone in front of the crack tip is modeled with a potential-based intrinsic cohesive zone approach. Here, SFNM is used to represent the kinematics of crack and the crack front inside the domain without the requirement of remeshing and discontinuous enrichment functions during crack growth, hence resolves the issues associated with the existing discrete numerical methods. A strain smoothing technique is adopted over the domain through which classical domain integration changes to line integration along each boundary of the smoothing cell, hence derivative of shape functions are not required in the computation of the field gradients, thus resolves the issue of element distortion. The proposed numerical framework is firstly verified using the patch test of the two-dimensional specimen under mode I and mode II loading conditions and subsequently extended for solving the two-dimensional standard fracture problems. The effectiveness of the proposed framework is checked by comparing the computational results with the available literature results.