Study On Mechanical Performance Of Engineering Fiber Reinforced Cementitious Composites PVA-ECC

Engineering Fiber Reinforced Cementitious Composites PVA-ECC is a high performance fiber reinforced Cement Composite. It has the strain hardening and micro slit characteristics under tensile load, Which Can overcome the faults of the low tensile strength, shear strength and seismic performance of concrete material, and it is a kind of green ecological building material, this material is expected to solve the problem of security and durability of the concrete. In this paper, the mechanical property of PVA –ECC is studied by a series of experiments. The main research contents as follows:(1) Based on uniaxial tension experiments, the influence of PVA fiber content by volume, water to binder ratio and sand binder ratio on strength and deformation of ECC was studied. The tensioned strain induration process of PVA-ECC was described reasonably. According to the uniaxial tensioned stress-strain curves, the stress-strain relationship before the strain softening of PVA-ECC had been simplified and appropriate tensile constitutive equation was deduced under uniaxial tension.(2) Based on splitting tension experiments, the influence of PVA fiber content by volume, water to binder ratio on strength and deformation of ECC was studied.According to the test results, the relationship between splitting tensile strength and uniaxial tensile strength was established.(3) Based on uniaxial compression experiments, the influence of PVA fiber content by volume, water to binder ratio, sand binder ratio, loading rate and specimen size on strength and deformation of ECC was studied. According to the test results, the relationship between axial compressive strength and the cube compressive strength was established. The uniaxial compression constitutive equation of PVA-ECC was put forward according to the axial compressive stress- strain curves.(4) The triaxial compression property of cylinder member, which has different water to binder ratio,was studied and the different confining pressure range 0 to 25 MPa,According to the test results, the ultimate tensile strength, peak value strain and relationship between the ultimate strain and lateral confining pressure of PVA-ECC was put forward. what’s more, regular triaxial tensioned constitutive equation of PVA-ECCwas put forward according to the stress strain curves.