钢纤维高强混凝土静、动力性能试验研究

Experimental research of static-dyanmic performance of steel fiber reinforced high-strength concrete

通过钢纤维高强混凝土的静力压缩和拉伸试验,研究了静压力作用下,钢纤维掺量对其抗压强度、弹性模量和泊松比的影响;研究了静拉力作用下钢纤维掺量对其抗拉强度影响;通过钢纤维高强混凝土的动态压缩试验,研究了形状效应、应变率效应对其动态抗压强度、极限应变和动力增大系数(DIF)的影响;通过动态劈裂试验研究了应变率效应对其动态抗拉强度、极限应变和动力增大系数(DIF)的影响.研究表明:2.5%的钢纤维能够显著提高混凝土的静力抗压强度、弹性模量,并能显著减小泊松比,对混凝土的抗拉强度也具有显著的增强作用;同时,动压力作用下,钢纤维高强混凝土的动态抗压强度、极限应变和DIF均随试件高径比的增大而提高;动态劈裂作用下,钢纤维高强混凝土动态抗拉强度、极限应变和DIF亦均随高径比的增大而提高.

This paper investigates the effect of steel fiber ratio on compression strength, elastic modulus and Poisson＇s ratio through the experiment of compression test and its tensile strength. Meanwhile, the effect of different shape and strain rate on steel fiber reinforced high-strength concrete dynamic compression strength, ultimate strain and DIF is studied through the experiments of dynamic compression test and dynamic splitting test strength test. It is shown that 2.5% steel fibers can significantly increase the compressive strength, elastic modulus of concrete, and reduce the Poisson＇s ratio. The tensile strength of concrete is also significantly enhanced by mixing 2.5% steel fibers.Additionally, under dynamic pressure, the dynamic compression strength, ultimate strain and DIF of steel fiber reinforced concrete increase with the improvement of height-diameter ratio. Meanwhile, dynamic splitting effect, dynamic tensile strength, ultimate strain and DIF have the same phenomenon.