基于内聚力模型的细观混凝土拉伸断裂行为分析  

Analysis of tensile fracture behavior of mesoscopic concrete based on cohesion modeling

作　　者：张博 ZHANG Bo(Lin Tong-Yan&Li Guo-Hao Consultants Shanghai Co.,Ltd.,Shanghai 200437,China)

机构地区：[1]上海林同炎李国豪土建工程咨询有限公司,上海200437

出　　处：《江苏建筑职业技术学院学报》2024年第3期9-14,共6页Journal Of Jiangsu Vocational Institute of Architectural Technology

摘　　要：基于内聚力单元对细观混凝土结构进行抗拉断裂模拟能够有效地反映细观组分的随机性对断裂过程的影响,但模型的细观参数往往通过模型调校得到。为了确保细观数值的可靠性和模型计算的精确性,对断裂数值模拟的关键参数ITZ强度进行分析,总结其对断裂本构关系的影响规律。结果表明:混凝土内部结构的不均匀性导致混凝土断裂行为的非线性;随着ITZ单元的抗拉强度提升,混凝土抗拉本构线弹性阶段明显延长,在相同的加载条件下,混凝土能够承受更大的应变而不发生断裂,表现出更好的变形能力和抗拉性能;混凝土结构的抗拉强度与ITZ抗拉强度呈现强烈的线性相关。The tensile fracture simulation of mesoscopic concrete structures based on cohesion element can effectively respond to the influence of the randomness of mesoscopic components on the fracture process,however,the mesoscopic parameters of the model are often obtained by model adjustment.In order to ensure the reliability of Mesoscopic parameters and the accuracy of model simulation,this paper analyzes the key parameter of fracture numerical simulation,ITZ strength,and summarizes its influence on the fracture constitutive relationship.The results show that:the unevenness of the internal structure of concrete leads to the non-linear fracture behavior of concrete;as the tensile strength of the ITZ element improves,the elastic phase of the concrete is obviously prolonged,and the concrete can withstand greater strains without fracture under the same loading conditions,showing better deformability and tensile properties;the tensile strength of the concrete structure and the ITZ tensile strength show a strong linear correlation.

关 键 词：混凝土 内聚力 断裂行为 ITZ强度 

分 类 号：TU528[建筑科学—建筑技术科学] U444[建筑科学—桥梁与隧道工程]