Determination of Stress Intensity Factor in Concrete Material Under Brazilian Disc and Three-Point Bending Tests Using Finite Element Method

摘要

Concrete is a brittle material with high compressive strength, low tensile strength and poor toughness, where cracks of different degrees and different forms can be developed, which compromises the durability and the lifetime of concrete structures. The crack starts to propagate in concrete when the crack tip stress intensity factor reaches the fracture toughness value (critical stress intensity factor K_C or fracture energy G_C). Many studies were carried out on the fracture of concrete to measure K_C and G_C based on LEFM (Linear Elastic Fracture Mechanics). This paper uses tow approaches to analyze the crack propagation of cracks three-point bending concrete beam and Brazilian disk with initial crack based on determination of stress intensity factor analytically starting from weight functions and numerically using the finite element software platform Abaqus.