Testing Research On Mechanical Properties Of Fiber Reinforced High-Strength Concrete

An experimental research on the behavior of fiber reinforced high-strength concrete under compression, split and direct shear was performed in this paper. The calculating methods and corresponding formulas which suit the characteristics of the mechanical properties of fiber reinforced high-strength concrete were put forward. The main achievements are as follows:1. Through the experiments on 63 plain and fiber reinforced high-strength concrete specimens with the dimensions of 100×100× 100mm, 63 of 150×150×150mm, 15 of 200 × 200 × 200mm and 126 of 150 ×150×300 mm, the effects of fibers of different types and volume fractions on cubic compressive strength, axial compressive strength and elastic modulus of high-strength concrete were studied. Influence coefficients of different types of fibers on compressive strength of high-strength concrete were put forward. The calculating formulas of compressive strength, the strength conversion coefficients of specimens with different dimensions and the relationship between elastic modulus and compressive strength were built.2.Through the experiments on 63 plain and fiber reinforced high-strength concrete specimens with the dimensions of 100 ×100 × 100mm and 63 of 150×150 × 150mm, effects of fibers of different types and volume fractions on splitting properties of the cubic specimens of high-strength concrete were studied. The relationship between splitting tensile strength and compressive strength, the effect of specimen size on splitting tensile strength and the effect of type and volume fractions of fibers on behavior of the deformation of split failure were investigated. The strengthening coefficients of different types of fibers on the splitting tensile strength of high-strength concrete were obtained. Calculating formulas of splitting strength and conversion coefficients of the strength of specimens with different dimensions were put forward.3.Based on the test research of 84 plain and fiber reinforced high-strength concrete specimens with the dimensions of 100 ×100× 400mm, the effects of fibers of different types and volume fractions on shear properties of high-strength concrete were studied. The relationships of shear strength with compressive strength as well as splitting tensile strength were analyzed and corresponding formulas were put forward. Influence coefficients of different type fibers on shear strength of high-strength concrete were given. Calculating expression of shear strength and shear transfer model were presented.The results of the experimental investigation reported hi this paper can provide useful data for compiling the technical regulation for fiber reinforced concrete in China.