添加不同纤维的高性能混凝土力学性能试验

通过试验研究了弹性模量具有明显差异的3种纤维对于混凝土的力学性能改善所起的作用，以及钢纤维、碳纤维和聚丙烯纤维单掺或复掺对于混凝土的抗压强度、劈裂抗拉强度和弹性模量的影响。结果表明：添加0．5％高弹性模量的钢纤维对于混凝土的强度和弹性模量均有提高作用，复掺0．3％钢纤维和0．2％碳纤维的混凝土抗拉强度的提高大于抗压强度；添加0．5％钢纤维的混凝土HPC-2的弹性模量最大，比基准混凝土提高6．5％；添加0．2％聚丙烯纤维的混凝土HPC-3的弹性模量最小，且小于基准混凝土；此外，混凝土抗压强度的影响程度与纤维的弹性模量的关系更为直接，混凝土劈裂抗拉强度的改善与纤维的抗拉强度的关系更为直接，纤维的弹性模量与基体弹性模量的比值，对复合材料的弹性模量有直接的影响。

Experiment on Mechanical Properties of High-performance Concrete with Different Fibers

The effect of three obvious different kinds of fibers on the mechanical properties of high-performance concrete was studied by the test. The compressive strength, splitting tensile strength and elastic modulus of the concrete were tested when steel, polypropylene and hybrid steel fiber were added to concrete respectively. The results indicate that the high elastic modulus of steel fibers with 0.5 % volume fraction will raise the strength and elastic modulus of concrete. When 0.3% carbon-steel fibers and 0.2~ carbon fibers are added to concrete, the incremental range of the tensile strength is bigger than that of the compressive strength. For the improvement of the concrete elastic modulus, the effect of 0.5% steel fibers of HPC-2 concrete is the most obvious, which is increased 6.5 % than basic concrete. The elastic modulus of HPC-3 concrete by adding 0.2% polypropylene fiber is the least, which is smaller than basic concrete. Moreover, the elastic modulus of fiber and tensile strength have direct effects on the compressive strength of concrete. The magnitude of ratio between the fiber elastic modulus and the concrete elastic modulus has direct effect on that of the fiber reinforced concrete.