高韧性PVA-FRCC单轴受压力学性能及本构关系

Study on Mechanical Performance and Constitutive Equation of High Toughness PVA-FRCC under Uniaxial Compression

通过单轴受压强度和变形特性试验,研究了聚乙烯醇(PVA)纤维体积掺量、粉煤灰及硅灰掺量对高韧性PVA纤维增强水泥基复合材料(PVA-FRCC)受压性能的影响;依据测得的抗压强度、弹性模量、泊松比以及单轴受压应力-应变全曲线,分别建立了立方体抗压强度与轴心抗压强度以及弹性模量的关系式;利用扫描电镜技术,对高韧性PVA-FRCC的微观结构进行了初步研究;基于实测应力-应变曲线的特点,提出了单轴受压本构方程,为高韧性PVA-FRCC结构非线性有限元分析及结构设计提供了理论依据.

Based on experimental results of strength and deformation under uniaxial compression, the influences of PVA fiber content by volume, fly ash and silica fume content on compression performance of PVA-FRCC with high toughness were investigated. The compressive strength, elasticity modulus, Poisson＇s ratio and the axial compressive stress-strain curves were obtained. According to test results, the relationship formula between cubic compressive strength and axial compressive strength, and between elasticity modulus and compressive strength were established. Using electron microscope, the microstructure of PVA-FRCC with high toughness was also observed. Furthermore, according to the complete test curves, an equation for the constitutive relationship of PVA-FRCC with high toughness was deduced under uniaxial compression, which is the theoretical basis on nonlinear finite element analysis and structure design.