钢纤维水泥基复合材料拱形试件断裂性能研究  

Study on the fracture properties of steel fiber reinforced cementitious composite arc specimen

作　　者：牛畅 卿龙邦 慕儒 赵楠 NIU Chang;QING Longbang;MU Ru;ZHAO Nan(College of Civil Engineering and Transportation,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学土木与交通学院,天津300401

出　　处：《混凝土》2022年第12期72-76,共5页Concrete

基　　金：国家自然科学基金(51779069,51878239);河北省教育厅重点基金(ZD2019072)。

摘　　要：基于电磁场方法制备了定向钢纤维增强水泥基复合材料拱形试件。通过带侧向约束的拱形三点弯曲断裂试验,研究了钢纤维增强水泥基复合材料的断裂性能。对比研究了定向及随机乱向试件的断裂参数及裂缝尖端应变演化全过程。研究结果表明,钢纤维增强水泥基复合材料拱形试件的荷载-裂缝口张开位移曲线可分为线弹性阶段、弹塑性阶段及后峰值阶段3个阶段;钢纤维增强水泥基复合材料拱形试件的起裂荷载和起裂韧度受纤维掺量的影响较小;与普通乱向钢纤维增强水泥基复合材料试件相比,定向钢纤维增强水泥基复合材料拱形试件的起裂韧度提高约40%,起裂断裂能提高超过50%。Based on the electromagnetic field method,the aligned steel fiber reinforced cementitious composite arc specimens were prepared in this study.Through the arc three-point bending fracture test with lateral constraint,the fracture performance of steel fiber reinforced cementitious composite arc specimens was studied.The fracture parameters of the aligned and randomly distributed steel fiber reinforced cementitious composite arc specimens and the entire process of the strain evolution at the crack tip were studied comparatively.The results show that the load-crack opening displacement curve of steel fiber reinforced cementitious composite arc specimens is divided into three stages,linear elastic stage,elastoplastic stage and post-peak stage.The initial cracking load and the initiation fracture toughness of the steel fiber reinforced cementitious composite arc specimens show little impact onfiber volume fraction.Compared with randomly distributed steel fiber reinforced cementitious composite arc specimen,the initiation toughness of the aligned steel fiber reinforced cementitious composite arc specimen is increased by about 40%,and the initiation fracture energy is increased by more than 50%.

关 键 词：水泥基复合材料 拱形试件 侧向约束 钢纤维 断裂参数 

分 类 号：TU528.041[建筑科学—建筑技术科学]