PVA纤维混凝土的单轴抗压应力应变关系

The Stress-strain Relationship of PVA Fiber Concrete under Uniaxial Compression

利用SHT4106电液伺服电子万能试验机对五组不同纤维掺量和LHFRC(层布式混杂纤维混凝土)及LSFRC(层布式钢纤维混凝土)立方体试块进行了单轴抗压试验。通过对试验结果的分析,表明PVA(聚乙烯醇)纤维能略微提高混凝土的抗压强度,但由于纤维的掺入会将部分空气带入混凝土基体中,减小粘接力,因此纤维的掺量不宜过大,最佳掺量在1%以下。PVA纤维能有效的改善混凝土立方体抗压变形能力,使混凝土由脆性破坏转换为有一定塑性的破坏形态,而LHFRC与素混凝土的应力应变曲线相差不多。但是LSFRC则表现出高强混凝土的应力应变曲线特点,即上升阶段基本上已经由曲线变成了直线,下降阶段比较陡,甚至可以认为不再有下降阶段。

Using SHT4106electro-hydraulic servo universal testing machine,the paper conducted uniaxial compression tests on five groups of different fiber content LHFRC（layer hybrid fiber reinforced concrete）and LSFRC（Layered just fiber reinforced concrete）test cubes.The analysis of test results indicates that PVA fibers can slightly increase the compressive strength of concrete,However,Because of the incorporation of the fibers into the air will be part of the concrete matrix,this can reduce the force of the substrate.Therefore,the blending amount should not be too large,and the best content is below 1%.PVA fiber can effectively improve the concrete cube compressive deformation,making the concrete convert from brittle failure to a certain plasticity of failure modes.But LSFRC showed a stress-strain curve characteristic of high strength concrete.The rising phase has basically become a straight line and the declining phase is relatively steep,which can be even considered as non-declining.