弯曲荷载下橡胶集料混凝土的细观断裂机制  

Meso-fracture Mechanism of Rubber Aggregate Concrete under Bending Load

作　　者：蔡祥磊 刘来宝[1] 王伟龙 张红平[1] CAI Xianglei;LIU Laibao;WANG Weilong;ZHANG Hongping(School of Materials and Chemistry,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;School of Transportation,Civil Engineering&Architecture,Foshan University,Foshan 528225,Guangdong,China)

机构地区：[1]西南科技大学材料与化学学院,四川绵阳621010 [2]佛山科学技术学院交通与土木建筑学院,广东佛山528200

出　　处：《西南科技大学学报》2022年第2期29-34,共6页Journal of Southwest University of Science and Technology

基　　金：国家自然科学基金青年基金(51808464);国家自然科学基金面上项目(51978590)。

摘　　要：为了研究弯曲荷载下橡胶集料混凝土的破坏机制,建立了橡胶集料在混凝土中微区作用的细观数值模型,模拟验证了四点弯曲荷载下橡胶集料混凝土内部的裂纹萌生及扩展破坏过程。结果表明:弯曲荷载下普通混凝土、掺橡胶集料混凝土的抗折强度的细观数值模型计算值与实测值的误差分别为2.38%,0.17%;混凝土的峰值位移随橡胶集料掺量的增加先增大后减小,最佳掺量约为20%等体积替换细骨料,对应提高峰值位移66.7%,橡胶集料粒径越小,峰值位移越大。通过橡胶集料混凝土的细观数值模型分析了橡胶集料改善混凝土断裂性能的机制。In order to study the failure mechanism of rubber aggregate concrete under bending load,a mesoscopic numerical model of the effect of crumb rubber in concrete was established.The process of crack initiation and propagation in rubber aggregate concrete under four-point bending load was verified by simulation.The result shows the error between the calculated value and the measured value of the mesoscopic numerical model of the flexural strength of ordinary concrete and concrete mixed with rubber aggregate under bending load is 2.38%and 0.17%,respectively.The peak displacement of concrete increases first and then decreases with the increase of rubber aggregate content.The optimal dosage is about 20%equal volume to replace fine aggregate,the corresponding peak displacement is 66.7%increased.The smaller the rubber aggregate particle size is,the higher the peak displacement is.The mechanism of rubber aggregate which may improve the fracture performance of concrete is analyzed through the meso-numerical model of rubber aggregate concrete.

关 键 词：橡胶集料混凝土 内聚力模型 细观数值模型 断裂机制 

分 类 号：TU528.2[建筑科学—建筑技术科学]