Constitutive Relation of Fiber Reinforced Concrete under Uniaxial Compression

The uniaxial compressive experiment of steel fiber reinforced concrete cylinder was carried out by microcomputer controlled electro-hydraulic servo pressure testing machine, which studied the effects on the types of steel fiber, fiber volume fraction and concrete strength grade to uniaxial compressive behavior of steel fiber reinforced concrete. The results showed that steel fibers can significantly improve the compressive strength, peak strain of concrete, and ultimate compressive strain. The growth rate increases with the increase of steel fiber mix proportion, and decreases with the increase of concrete strength grade. Based on the test results, the calculated formulas of axial compression strength and peak strain of different types of steel fiber concrete were revised, and their rationality was verified by comparison with the test results. For the stress-strain curve, a suitable constitutive relationship model was selected. Comparison with the test curve proved that the model can better describe the whole process of steel fiber concrete under uniaxial compression.