考虑钢纤维分布的SFRS抗压特性

对于喷射钢纤维混凝土(SFRS)材料,已有数值模拟或将其简化为均质材料或没有合理地考虑钢纤维的空间分布特性,导致相关数值建模未能很好地反映其实际力学行为。本文提出一种SFRS材料中钢纤维生成方法,开展数值模拟分析了钢纤维取向、含量和长径比对SFRS材料抗压性能的影响。结果表明:沿受力方向分布钢纤维能更好地发挥抗力作用,突显了SFRS材料的力学性能方向性特征;钢纤维对混凝土的抗压强度略有提高,但能明显影响混凝土裂缝发展阶段和破坏阶段的力学性能,钢纤维的掺入使混凝土的延性和破坏后变形能力提高1倍左右。

Compressive Behavior of SFRS Considering the Distribution of Steel Fibers

The steel fiber reinforced shotcrete (SFRS) was either simplified into the homogeneous material or analyzed without considering the realistic distribution characteristics of steel fibers, so that the corresponding numerical simulations cannot appropriately reflect the actual mechanical properties of SFRS components. A generation approach of steel fibers in SFRS is developed, and numerical simulations are performed to study the effects of the orientation, content and length-to-diameter ratio of steel fibers. Numerical analysis results indicate that: distributing the steel fibers along the loading direction can enhance the resistance of SFRS and exhibit the directionality of mechanical behavior of SFRS materials; steel fibers can improve the compressive strength of concrete slightly. However, it can obviously affect the mechanical properties of concrete in crack development stage and failure stage. The addition of steel fiber can increase the ductility and post-failure deformation capacity of concrete by about one time.