Abstract

Among the various polymer fibers available, polypropylene (PP) fibers are often used to improve the impermeability, impact resistance, anti-wear and crack resistance of concrete. In order to improve the interfacial adhesion between PP fibers and cement a series of PP composite fibers were prepared by melt spinning with micro-silica (MSi) as a hydrophilic modifier and the structure and properties of the composite fibers were studied. The results showed that the composite fibers displayed rougher and more hydrophilic surfaces than the pure PP fibers. As revealed by single fiber pull-out tests, the interfacial adhesive strength between the PP fibers and a cement matrix increased obviously after adding the MSi to the PP fibers. The flexural strength and compressive strength of the cement mortar blended with the composite fibers were much better than those of the cement modified by pure PP fibers. The cement mortar enhanced by the composite fibers containing 10 wt.% of MSi showed the best mechanical strength, which we suggest was caused by a balance between fiber strength and interfacial adhesive strength. In general, our research indicated that the mechanical properties of PP fiber reinforced cement-based materials could be further enhanced by mixing appropriate amounts of MSi in the PP fibers which provides a novel strategy to design high-ρperformance materials for modern architecture.

抽象的

在各种可用的聚合物纤维中，聚丙烯（PP）纤维通常用于改善混凝土的抗渗性，抗冲击性，抗磨性和抗裂性。为了提高聚丙烯纤维与水泥之间的界面粘结性，以微二氧化硅（MSi）为亲水改性剂，通过熔融纺丝制备了一系列聚丙烯复合纤维，并对复合纤维的结构和性能进行了研究。结果表明，复合纤维比纯PP纤维具有更粗糙，更亲水的表面。正如单纤维拉出试验所揭示的，在将MSi加入PP纤维后，PP纤维与水泥基体之间的界面粘合强度显着提高。掺有复合纤维的水泥砂浆的抗折强度和抗压强度比纯聚丙烯纤维改性的水泥要好得多。由含10％（重量）MSi的复合纤维增强的水泥砂浆显示出最佳的机械强度，我们认为这是由于纤维强度和界面粘合强度之间的平衡所致。总体而言，我们的研究表明，通过在PP纤维中掺入适量的MSi可以进一步增强PP纤维增强水泥基材料的机械性能，这为设计用于现代建筑的高性能高性能材料提供了一种新颖的策略。我们认为这是由纤维强度和界面粘合强度之间的平衡引起的。总体而言，我们的研究表明，通过在PP纤维中掺入适量的MSi可以进一步增强PP纤维增强水泥基材料的机械性能，这为设计用于现代建筑的高性能高性能材料提供了一种新颖的策略。我们认为这是由纤维强度和界面粘合强度之间的平衡引起的。总体而言，我们的研究表明，通过在PP纤维中掺入适量的MSi可以进一步增强PP纤维增强水泥基材料的机械性能，这为设计用于现代建筑的高性能高性能材料提供了一种新颖的策略。