基于率相关内聚力本构模型的混凝土细观单轴受拉性能  

Mesoscopic Uniaxial Tensile Properties of Concrete Based on Rate-Dependent Cohesive Constitutive Model

作　　者：肖诗云[1] 王杨[1] XIAO Shi-yun;WANG Yang(School of Infrastructure Engineering,Dalian University of Technology,Dalian 116024,China.)

机构地区：[1]大连理工大学建设工程学院,辽宁大连116024

出　　处：《东北大学学报（自然科学版）》2023年第11期1647-1654,1662,共9页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(51878113)。

摘　　要：混凝土宏观率相关效应研究已经取得了十分丰富的成果,其细观结构和材料参数显著影响混凝土宏观力学性能,因此,从细观尺度研究混凝土动态性能是揭示混凝土宏观率相关效应的重要途径.本文引入应变率影响,修正界面内聚力本构模型,从细观尺度研究了不同骨料含量和骨料形状的混凝土在不同加载速率下的单轴抗拉破坏模式和力学特性.分析结果表明:随着加载速率增加,混凝土破坏裂缝分布更加均匀;混凝土抗拉强度的增量与应变率的对数呈线性关系;混凝土抗拉强度随骨料含量增加近似线性减小,但骨料形状对其影响很小.The research on macroscopic rate-dependence of concrete has achieved very rich results,and its meso structural and material parameters significantly affect the macroscopic mechanical properties of concrete.Therefore,studying the dynamic properties of concrete at the meso-scale is an important way to reveal the macroscopic rate-dependence of concrete.In this paper,the influence of strain rate was introduced to modify the interfacial cohesion constitutive model,and the uniaxial tensile failure mode and mechanical properties of concrete with different aggregate content and shapes were studied under various loading rates from the mesoscale.The results show that the distribution of failure cracks becomes increasingly uniform with the increase of loading rate.The increment in tensile strength of concrete exhibits a linear relationship with the logarithm of strain rate.The tensile strength of concrete decreases linearly with an increase in aggregate content,while the aggregate shape has little effect on it.

关 键 词：混凝土 内聚力本构模型 加载速率 随机骨料模型 单轴受拉 

分 类 号：TU528.1[建筑科学—建筑技术科学]