预应力钢筒混凝土管接头灌注砂浆的抗裂性研究

摘要

通过圆环法试验,研究了养护条件、矿物掺合料、聚丙烯纤维、膨胀剂、玄武岩纤维和内养护材料等因素对砂浆抗裂性的影响.研究结果表明,有无养护对砂浆的抗裂性影响显著,单掺玄武岩纤维可提高灌注砂浆的抗裂性,陶砂、高吸水性树脂等内养护材料、膨胀剂与玄武岩纤维等共同作用下,灌注砂浆的开裂时间延长60%～130%,验证了从砂浆内养护角度出发来提高砂浆抗裂性的可行性.%In this paper,the ring test was used to study the influence of curing conditions,mineral admixture, polypropylene fiber,expansion agent, basalt fibers and internal curing material on crack resistance of mortar.The results show that the conservation of mortar has a significant effect on the crack resistance.Singledoped basalt fiber can increase the crack resistance for grouting mortar.The cracking time of mortar will extend from 60％ to 130％ under the combined action of expansion agent,basalt fiber and internal curing materials such as clay sand and super absorbent polymer.Therefore,it is feasible to improve the crack resistance by internal curing.