定向钢纤维增强水泥基复合材料抗拉细观模拟

将钢纤维增强水泥基复合材料看作水泥砂浆基体和钢纤维夹杂组成的复合材料,采用扩展有限元法模拟了定向钢纤维增强水泥基复合材料受拉破坏的全过程.研究采用混合同余法生成随机数建立了钢纤维随机生成算法,进而生成了不同纤维掺量的定向钢纤维水泥砂浆细观数值模型.在考虑钢纤维与砂浆基体黏结滑移作用的基础上,模拟了定向钢纤维水泥砂浆受拉断裂全过程,得到了拉伸应力-应变全曲线.通过开展直拉试验,对细观数值模拟结果进行了验证.研究表明,细观数值模拟得到的全曲线结果与试验结果吻合较好,建立的细观模型有助于进一步揭示钢纤维增强水泥基复合材料的拉伸破坏机理.

Meso Scale Simulation of Tension Properties for Aligned Steel Fiber Reinforced Cementitious Composites

Steel fiber reinforced cementitious composites(SFRC) were treated as composite material, which consists of steel fiber and cement mortar. The whole process of tensile fracture for aligned steel fiber reinforced cementitious composites(ASFRC) was simulated on the basis of extended finite element method(XFEM). Mixed congruence algorithm was used to generate random number, and random generation algorithm of steel fibers was established, the numerical models with different content of steel fibers were established. Considering bond slip between steel fiber and mortar matrix, the whole process of tensile fracture for ASFRC was simulated, and the stress strain curves were obtained. The numerical simulation results were verified by conducting tension tests. The research shows that the complete curve results of numerical simulation match well with experimental results, the meso scale numerical model can contribute to reveal the tensile failure mechanism of SFRC.