工程纤维增强水泥基复合材料PVA-ECC力学性能研究

发布时间：2018-01-16 03:25

本文关键词：工程纤维增强水泥基复合材料PVA-ECC力学性能研究　出处：《河南理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：工程纤维增强水泥基复合材料(Engineered Fiber Reinforced Cementitious Composites)PVA-ECC,是一种高性能纤维增强水泥基复合材料,在拉伸荷载作用下具有应变-硬化和多微缝开裂特性,克服了现有混凝土材料的抗拉、抗剪强度低,抗震性能较差的缺点,是一种环保生态型建筑材料。该材料有望解决混凝土所面临的安全性、耐久性问题,本文通过试验对PVA-ECC的力学性能进行了一系列的研究,主要研究内容如下:(1)通过单轴抗拉性能试验,研究了PVA纤维体积率、水胶比、砂胶比等对PVA-ECC单轴受拉强度和变形的影响,合理描述了PVA-ECC受拉应变硬化过程。根据实测单轴受拉应力-应变曲线的特点,对PVA-ECC应变软化前的应力-应变关系进行了合理地简化,并提出了相应单轴受拉本构方程。(2)通过劈裂抗拉性能试验,研究了PVA纤维体积率、水胶比等对PVA-ECC劈裂抗拉强度和变形的影响,根据所测得的试验结果,建立了劈裂受拉强度与单轴受拉强度之间的关系。(3)通过单轴受压性能试验,研究了PVA纤维体积率、水胶比、砂胶比、加载速率、尺寸效应等对PVA-ECC单轴受压强度和变形的影响;根据所测得的试验结果,建立了轴心抗压强度与立方体抗压强度的关系;并根据实测轴心受压应力-应变曲线的特点,提出了PVA-ECC单轴受压本构方程。(4)通过常规三轴受压性能试验,研究了不同水胶比下的圆柱体试件在0~25MPa不同围压下的常规三轴受压性能,根据所测得的试验结果,建立了PVA-ECC极限抗压强度、峰值应变、以及极限应变与侧向围压之间的关系,并根据实测应力-应变曲线,提出了PVA-ECC常规三轴受压本构方程。
[Abstract]:Engineering fiber reinforced cement composite (Engineered Fiber Reinforced Cementitious Composites PVA-ECC), is a kind of high performance fiber reinforced cement composites under tensile load with strain hardening and multiple cracking characteristics, overcomes the defects of the existing concrete tensile strength, low shear strength, seismic performance is poor, is a kind of environmental ecological building materials. The material is expected to solve the safety of concrete facing, the durability problem, this paper through a series of mechanical performance test of PVA-ECC, the main research contents are as follows: (1) the performance of uniaxial tensile test of PVA fiber volume ratio, water binder ratio, ratio on the PVA-ECC of uniaxial tensile strength and deformation affected by sand adhesive, reasonable description of the tensile strain hardening process by PVA-ECC. According to the measured uniaxial tensile stress strain curve, the PVA-ECC should be The strain softening stress-strain relations are reasonably simplified, and put forward the corresponding uniaxial tension constitutive equation. (2) by splitting tensile performance test of PVA fiber volume ratio, water cement ratio on the PVA-ECC splitting effect and deformation of the tensile strength, according to the test results measured the established relationship between splitting tensile strength and uniaxial tensile strength. (3) the performance of uniaxial compression test of PVA fiber volume ratio, water cement ratio, sand cement ratio, loading rate, size effect and deformation effect on uniaxial compressive strength test according to PVA-ECC; the measured results, to establish the relationship between the compressive strength and compressive strength; and the characteristics of stress-strain curve according to measured axial compression, the constitutive equation of PVA-ECC under uniaxial compression. (4) by conventional three axis compression performance test of different water binder ratio of cylinder specimen In the 0~25MPa under different confining pressure of the conventional three axis compression performance, according to the test results measured, established the compressive strength, peak strain and PVA-ECC limit, limit strain and confining pressure relationship between, and according to the measured stress-strain curves, the constitutive equation of PVA-ECC conventional three axis compression.

【学位授予单位】：河南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528

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