基于相场理论的混凝土梁断裂数值模拟研究

Research on Numerical Simulation of Concrete Beam Fracture Based on Phase Field Theory

混凝土是以砂浆与骨料为主要成分的一种非均质、准脆性复合材料,断裂失效是工程中的常见问题,相场法是近年来兴起的一种新型断裂模拟方法,实现了裂纹的萌生、扩展、分叉、融合,在模拟复杂裂纹形态上展现出巨大优势。本文基于相场理论方法通过ABAQUS软件对混凝土梁断裂性能进行模拟研究,首先,验证相场法的相场特征宽度l_(0)和网格尺寸h的敏感性;其次,验证了混凝土梁断裂裂纹形态、内部力–裂缝张口位移响应曲线(P-CMOD)与文献模拟结果的稳健性;最后,模拟分析五种不同厚度的混凝土梁的断裂性能。结果表明相场法适用于混凝土梁厚度的断裂研究。

Concrete is a non-homogeneous,quasi-brittle composite material mainly composed of mortar and aggregate.Fracture failure is a common problem in engineering.The phase field method is a new type of fracture simulation method that has emerged in recent years.It has achieved crack initiation,propagation,branching,and merging,showing great advantages in simulating complex crack shapes.This paper uses the phase field theory method to simulate the fracture performance of concrete beams through the ABAQUS software.First,the sensitivity of the phase field characteristic length l_(0) and mesh size h is verified.Secondly,the robustness of the fracture crack morphology,internal force-crack mouth opening displacement response curve(P-CMOD)of the concrete beam fracture is verified against the simulation results in the literature.Finally,the fracture performance of five concrete beams of different thicknesses is simulated and analyzed.The results show that the phase field method is suitable for fracture research of concrete beams of different thicknesses.