聚丙烯纤维增强再生混凝土的抗压与抗拉性能研究

Study on Compressive and Tensile Properties of Polypropylene Fiber Reinforced Recycled Concrete

由废弃混凝土骨料配制而成的再生混凝土存在孔隙率大、吸水率高及密度较低等不足,抗压与抗拉等基本力学性能与天然混凝土有一定的差距,极大地限制了其推广应用。基于聚丙烯纤维的阻裂效应,通过采用普通混凝土配合比设计方法,制备获得聚丙烯纤维增强再生混凝土,并制作标准立方体试块对其开展抗压和劈拉试验。结果表明,聚丙烯纤维增强再生混凝土的抗压和抗拉强度与纤维掺量具有正相关关系,但与再生骨料掺量表现为负相关关系;随着再生骨料掺量的增加,聚丙烯纤维对再生混凝土的增强作用逐渐变小;相较于再生混凝土的抗压强度,聚丙烯纤维对再生混凝土抗拉强度的增强作用表现得更为显著。

Recycled concrete made from waste concrete aggregate has shortcomings such as high porosity,high water absorption and low density,the basic mechanical properties such as compression and tension differ from natural concrete,greatly limits its popularization and application.Based on the crack resistance effect of polypropylene fiber,the recycled concrete reinforced by polypropylene fiber was prepared by adopting the mix design method of ordinary concrete,and the standard cube test block was made to carry out the compression and splitting tensile tests on it.The results show that the compressive and tensile strength of polypropylene fiber reinforced recycled concrete has a positive correlation with the fiber content,but a negative correlation with the recycled aggregate content;With the increase of recycled aggregate content,the strengthening Effect of polypropylene fiber on recycled concrete gradually decreases;Compared with the compressive strength of recycled concrete,polypropylene fiber has a more significant Effect on the tensile strength of recycled concrete.