钢丝直径对双丝拉拔混凝土力学性能影响的三维数值模拟研究

3D Numerical Modeling of Fiber Diameter Effect on Performance of Twin Fibers Pullout Test

考虑三维状态下界面、钢丝和混凝土基体三相材料力学性能参数的细观非均匀分布,利用ANSYS和RFPA3D(Realistic Failure Process Analysis)有限元程序建立了双丝拉拔混凝土模型,研究了钢丝直径对双丝拉拔混凝土力学性能的影响以及界面的作用机理,实现了材料试件从细观损伤到宏观破坏的全过程三维分析,获得了试件峰值荷载、韧度以及声发射数与钢丝直径的关系。结果表明:钢丝的脱粘速度随钢丝直径的增加而增加;工程中使用同等体积的钢材,小直径钢丝试件具有更大的抗拔力以及拉拔韧性,其性价比更高。

The coupling among fibers and meso-level heterogeneous distribution of each phases of composite material were investigated.Numerical models for twin fibers pull-out test were simulated by using finite element methods like ANSYS and RFPA3 D.The influence of fiber diameters on mechanical properties and mechanism of interface was studied on twin fibers pull-out test specimens.The complete process from meso-level damage to macro failure was simulated.The relationship of peak load,relative toughness,and acoustic emission energy versus fiber diameter were established,which indicates that the split speed increases when fiber diameter increases.Furthermore,with same volume of steel in the project,higher tensile strength and tensile toughness could be obtained if using steel fiber with small diameter,which is more cost effective.