钢纤维高强混凝土轴拉应力-应变曲线试验研究

Stress-strain Behavior for High-strength Steel Fiber Reinforced Concrete under Tensile Loading

钢纤维高强混凝土,可以大大改善高强混凝土的脆性,进而提高构件的延性和抗震性能。为研究钢纤维高强混凝土轴心抗拉性能,设计了合适的轴心抗拉全过程试验方案,然后分别对强度等级为C60和C80,钢纤维体积率为0%、1.0%、1.5%和2.0%的钢纤维高强混凝土进行轴心抗拉全过程试验。根据试验结果,分析了混凝土强度和钢纤维体积率对于改善混凝土抗拉强度、峰值应变的影响;提出了适用的钢纤维高强混凝土轴拉应力-应变曲线数学表达式。提出的计算公式与试验结果吻合较好,可以为钢纤维高强混凝土结构的设计和非线性分析提供理论基础。

High-strength steel fiber reinforced concrete （HSSFRC） has high strength along with good toughness, and thus enhances seismic performance of structures. In this paper, uniaxial tensile experiment for HSSFRC under monotonic loading was conducted in order to study the tensile properties. The volume fractions of steel fiber are 0% ,1.0% , 1.5% and 2.0% with the cube compressive strength of 60 MPa and 80 MPa, respectively. The effects of steel fiber volume fractions on uniaxial tensile strength and strain corresponding to the peak stress of HSSFRC were investigated. Based on the test data, a more suitable analytical model is proposed to generate the stress-strain curve of HSSFRC, which fits well with the experimental curves and can be used for nonlinear analysis of structures or components.