基于双K准则的不同掺量铁尾矿砂混凝土断裂特性研究

Fracture characteristics of ferrous tailings concrete with different content based on double-K criterion

基于双K准则开展对铁尾矿砂混凝土断裂行为的研究。通过对5组铁尾矿砂掺量分别为0、25%、50%、75%、100%的铁尾矿砂混凝土标准三点弯曲梁试件进行断裂试验,测定各组试件的P-CMOD曲线和P-ε曲线,确定相关断裂参数。结果表明:普通混凝土与铁尾矿砂混凝土的断裂过程与破坏形态相近;铁尾矿砂用量的增加对起裂荷载与起裂韧度的提高程度比失稳荷载与失稳韧度更加显著;铁矿砂混凝土的延性略显逊色。

Based on double-K criterion,the fracture behavior of ferrous tailings concrete was researched.Through the fracture test of 5groups of standard three-point bending beam specimens with ferrous tailing sand content of 0,25%,50%,75% and 100% respectively,the P-CMOD curve and P-ε curve of each specimen were measured,then the fracture parameters were acquired.Results revealed that fracture process and failure mode of ordinary concrete and ferrous tailings concrete were similar.The amount of ferrous tailings sand increased the initial cracking load and initial cracking toughness more significantly than that of unstable cracking load and unstable cracking toughness.The ductility of ferrous tailings concrete was slightly inferior.