钢纤维含量对高性能混凝土断裂性能影响的试验研究及评价分析

Experimental Study and Evaluation Analysis on Influence of Steel Fiber Content on Toughness Properties of High Performance Concrete

为研究不同掺量钢纤维对高性能混凝土断裂韧度的影响,对高性能纤维混凝土单边切口梁进行了三点弯曲试验,共进行了三组不同掺量的钢纤维混凝土单边切口试件的断裂试验及混凝土基本物理力学性能试验,并根据双K断裂准则进行韧度计算。结果表明,钢纤维的掺量是影响高性能混凝土断裂韧度的一个重要影响因素。高性能混凝土的断裂韧度随着钢纤维掺量的增加而提高,其中,钢纤维掺量为2%和4%的混凝土,其断裂韧度平均值分别是不掺量混凝土的9.5倍和10.6倍。在固定基质混凝土配合比条件下,钢纤维掺量为2%时,高性能混凝土的抗压强度、抗弯强度、流动性、以及断裂韧度等性能综合最优。

In order to study the effect of steel fiber content on the fracture toughness of high performance concrete, three-point bending tests of single edge notched beams made of steel fiber reinforced high performance concrete（SFHPC） were performed. The basic physical parameters of concrete were obtained by experiments. Meanwhile, fracture toughness of high performance concrete with different steel fiber content were determined by three-point bending tests and doublc-K fracture criterion. The results show that the content of steel fiber is an important factor that influences the fracture toughness of high performance concrete. The fracture toughness of high performance concrete increases with the increasing of steel fiber content, and the average fracture toughness of concrete with steel fiber content of 2% and 4% is 9.5 and 10.6 times to the content of 0 respectively. In the fixed matrix concrete mix ratio conditions, the compressive strength, fluidity, and fracture toughness of high performance concrete are optimized with the steel fiber content of 2%.