橡胶粒径及掺量对混凝土断裂韧性的影响

Influence of rubber particle size and content on fracture toughness of concrete

为研究橡胶粒径及掺量对混凝土断裂韧性的影响规律,对不同粒径(30、50目),不同掺量(0、5%、10%、15%、20%)的橡胶混凝土试件进行了楔入劈拉试验,计算得到橡胶混凝土试件起裂韧度、失稳断裂韧度随橡胶粒径及掺量的变化规律。结果表明,掺入橡胶后,混凝土的起裂韧度随橡胶掺量增加呈线性降低,橡胶掺量低于15%的混凝土,失稳断裂韧度高于基准混凝土,20%掺量的橡胶混凝土失稳断裂韧度小于基准混凝土,失稳断裂韧度与橡胶掺量呈高阶函数关系。掺50目橡胶的混凝土试件失稳断裂韧度高于30目橡胶混凝土,表现出更好的断裂韧性。

In order to study the influence of rubber particle size and content on the fracture toughness of concrete,wedge splitting tensile tests were carried out on rubber concrete specimens with different particle sizes(30 mesh,50 mesh)and different contents(0,5%,10%,15%,20%),and the variation rules of fracture toughness and unstable fracture toughness of rubber concrete specimens with rubber particle size and content were calculated.The results show that the crack initiation toughness of concrete decreases linearly with the increase of rubber content.The results show that the fracture toughness of concrete with rubber content less than 15%is higher than that of reference concrete,and the fracture toughness of rubber concrete with 20%rubber content is lower than that of reference concrete.The relationship between fracture toughness and rubber content presents higher order function.The instability fracture toughness of concrete with 50 mesh rubber is higher than that of 30 mesh rubber concrete,showing better fracture toughness.