国家自然科学基金资助项目(51208183)；河南省科技攻关项目(132102310312)；河南省自然科学研究计划项目(12B560006)
以劈裂抗拉强度和变形性能为主要评价指标，研究了聚乙烯醇（PVA）纤维体积分数及水胶比对工程纤维增强水泥基复合材料（ECC）劈裂全程荷载变形曲线与劈裂抗拉强度的影响规律.结果表明：PVA纤维体积分数达到15%后，纤维的增强阻裂作用较为明显，横跨裂缝的PVA纤维可通过“桥接”作用继续承担和传递拉力，使PVAECC试件在劈裂拉伸荷载作用下具有明显的变形强化特性，且其峰值抗拉强度和峰值变形明显增大，延性得到显著改善；水胶比越大，试件在劈裂裂缝处的PVA纤维越易拔出，其峰值变形明显增大，试件破坏时具有明显的塑性特征.基于测得的材料抗拉强度，分析了2种垫条方式下所测试件劈裂抗拉强度之间的关系及其与轴心抗拉强度的关系.
Based on splitting tension test of engineered fiber reinforced cementitious composites（ECC） with different polyvinyl alcohol（PVA） fiber volume fractions and water binder ratios, the load deformation curve and splitting tensile strength were investigated. Results show that after PVA fiber volume fraction reaches 15%, the effects of fiber on strengthening and crack resistance are more obvious. PVA fibers can bear and transfer tension through the strong bridging effect, so PVA ECC specimens have obvious deformation strengthening characteristics under splitting tension. Furthermore, the peak tensile strength and peak deformation of specimens are increased and the ductility of specimens is improved significantly. When water binder ratio increases, PVA fibers are more likely to be pulled out, so the increase of PVA ECC peak deformation is obvious and specimens have obvious characteristics of plastic failure. Splitting tensile strength tested by the two different spacer methods was analyzed and the relationship between axial tensile strength and splitting tensile strength was established.
刘泽军,李艳,温丛格. PVAECC劈裂抗拉强度与变形性能试验研究[J].建筑材料学报,2016,19(4):746-751
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