钢纤维对聚氨酯砂浆力学性能及弯曲韧性的影响  

Effect of Steel Fiber on Mechanical Properties and Flexural Toughness of Polyurethane Mortar

作　　者：朱涵[1,2] 姜金龙 姜雯丽霞 邵建文 ZHU Han;JIANG Jinlong;JIANG Wenlixia;SHAO Jianwen(School of Civil Engineering,Tianjin University,Tianjin,China,300350;Coastal Civil Engineering Structure and Safety Key Laboratory of the Ministry of Education,Tianjin University,Tianjin,China,300072)

机构地区：[1]天津大学建筑工程学院,天津300350 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072

出　　处：《沈阳建筑大学学报（自然科学版）》2021年第1期95-103,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金青年科学基金项目(51708314)。

摘　　要：目的提高聚氨酯砂浆的强度,改善其脆性断裂特性,从而得到一种高性能路面快速修补材料。方法选用两种长径比(30、65)的钢纤维,分别以不同体积分数掺入到聚氨酯砂浆中,研究其对砂浆抗压抗折强度的影响规律;通过三点弯曲加载试验得到荷载挠度曲线,以峰值变形能、峰后变形能和弯曲韧性指数来评价砂浆的弯曲韧性。结果钢纤维体积分数在2%以下时,聚氨酯砂浆抗压抗折强度无明显影响,体积分数为3%、4%时,抗压抗折强度显著提高。结论钢纤维提高了砂浆的变形能力,砂浆由脆性破坏变为延性破坏,同时大幅度提升了聚氨酯砂浆的弯曲韧性,且长径比较大的钢纤维对砂浆的弯曲韧性增强效果更好。In order to increase the strength of polyurethane mortar and improve its brittle fracture characteristics,then obtain a high-performance pavement rapid repair material.Steel fibers with aspect ratio of 30 and 65 were incorporated into the polyurethane mortar by different volume fraction,to investigate the effect on the compressive strength,flexural strength and flexural toughness of mortar.The load deflection curve was obtained by the three-point bending load test,and the flexural toughness of mortar can then be evaluated in terms of the peak deformation energy,post-peak deformation energy and flexural toughness index.The results showed that:The compressive and flexural strength of polyurethane mortar changed little with a steel fiber volume fractionof 2%or less,the compressive and flexural strength increased significantly as the steel fiber volume fraction grows to 3%-4%.With the incorporation of steel fiber,the deformability of mortar increased,the failure mode showed obvious ductile fracture rather than brittle failure,and the flexural toughness was improved greatly as well.Furthermore,The mortar showed better flexural toughness with steel fibers of a larger aspect ratio.

关 键 词：聚氨酯砂浆 钢纤维 长径比 力学性能 弯曲韧性 

分 类 号：TU528[建筑科学—建筑技术科学]