纤维水泥砂浆与混凝土粘结性能双面剪切试验研究

Experimental research on two-sided shearing bonding property of fiber cement mortar to concrete

在砂浆中分别掺入聚乙烯醇纤维、聚丙烯纤维、钢纤维以及适量的外加剂制备纤维水泥砂浆。使用千斤顶对外包纤维水泥砂浆的混凝土构件进行双面剪切试验,研究纤维种类、混凝土强度、纤维水泥砂浆抗压强度对纤维水泥砂浆与混凝土界面粘结性能的影响。试验结果表明:掺聚乙烯醇纤维的水泥砂浆与混凝土界面的剪切强度最大,聚丙烯纤维次之,钢纤维最小;剪切强度随混凝土抗压强度的提高而增大,随纤维水泥砂浆抗压强度的提高而增大;剪切强度与纤维水泥砂浆抗压强度之间存在线性相关关系。本研究中的纤维种类较多,纤维水泥砂浆强度范围涉及较广,可以较好地为加固工程实际提供理论指导。

The fiber cement mortar was mixed respectively with polyvinyl alcohol fiber,polypropylene fiber,steel fiber and appropriate admixtures in the mortar. By using a jack to take the two-sided shearing experiments of concrete species covered by fiber cement mortar,the study aimed to investigate the influence of fiber types,strength of concrete and strength of fiber cement mortar on the bonding property between concrete and fiber cement mortar. The results of the experiments demonstrated that the shear strength between concrete and polyvinyl alcohol fiber cement mortar was the highest,that of polypropylene fiber took second place,and the shear strength between concrete and steel fiber was the low-est. It was concluded that the higher the compression strength of concrete or compression strength of fiber cement mortar was,the higher the shear strength was. There was a positive linear correlation between shear strength and compression strength of fiber cement mortar. Thus this study,with various types of fibers and a wide range of the fiber strength researched,could provide a theoretical guide for the practical reinforcement engineering.