高强钢绞线网增强ECC抗弯加固无损RC梁试验  

Experiment on non-damaged RC beams strengthened by high-strength steel wire strand meshes reinforced ECC in bending

作　　者：李可[1] 赵佳丽 李志强 朱俊涛[1] LI Ke;ZHAO Jiali;LI Zhiqiang;ZHU Juntao(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;China Construction Yipin Investment&Development Co.,Ltd.,Wuhan 430070,China)

机构地区：[1]郑州大学土木工程学院,郑州450001 [2]中建壹品投资发展有限公司,武汉430070

出　　处：《复合材料学报》2022年第7期3428-3440,共13页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(U1804137,51879243);中国博士后基金(2020M672236);河南省高等学校青年骨干教师培养计划(2020GGJS003)。

摘　　要：为研究高强钢绞线网增强工程水泥基复合材料(Engineered cementitious composites,ECC)加固钢筋混凝土(Reinforced concrete,RC)梁的受弯性能,考虑钢绞线直径、纵向钢绞线配筋率、ECC配方及端部锚固4个影响因素,对7个加固无损RC梁试件进行受弯试验。结果表明,在采用合理加固层端部锚固措施的情况下,通过高强钢绞线网增强ECC抗弯加固RC梁可显著提升其受弯承载力、延性、抗裂性,有效约束原RC梁的裂缝发展并减小裂缝宽度;纵向高强钢绞线配筋率的增大会提高加固梁的受弯开裂荷载、承载力、控裂能力、刚度,但试件配置过量的纵向高强钢绞线会降低加固梁的延性、韧性;在纵向高强钢绞线配筋率接近的情况下,采用直径较大的高强钢绞线,会在一定程度上降低加固梁的延性、韧性、控裂能力;加固梁的受弯开裂荷载、承载力、刚度随着ECC的弹性模量及抗拉强度的提高而增大;加固梁的控裂能力、延性、韧性随ECC极限拉应变提高而增大。In order to study the flexural performance of reinforced concrete(RC) beams strengthened by highstrength steel wire strand(HSSWS) meshes reinforced engineered cementitious composites(ECC), the bending tests were performed on seven non-damaged RC beams considering the influence factors such as the steel strand diameter, the longitudinal steel strand reinforcement rate, formula of ECC and end anchorage. The results show that under the condition of using reasonable anchorage measures at the end of the reinforcement layer, the bearing capacity, ductility and crack-control capacity of RC beams strengthened by HSSWS meshes reinforced ECC in bending can be significantly improved, and the crack development of the original RC beam can be effectively delayed,which results in reducing crack width. The increase of longitudinal HSSWS reinforcement rate will improve the cracking load, bearing capacity, crack-control capacity and stiffness of the strengthened beams in bending, but excessive HSSWS reinforcement rate of the strengthened beams would reduce the ductility and toughness. When the reinforcement ratio of longitudinal HSSWS is close, the ductility, toughness and crack-control ability of strengthened beams would be reduced to some extent by using the HSSWS with relative large diameter. The cracking load, bearing capacity and stiffness of strengthened beams in bending increase with the increases of elastic modulus and tensile strength of ECC. The crack-control ability, ductility and toughness of strengthened beams increase with the increase of ultimate tensile strain of ECC.

关 键 词：高强钢绞线网增强ECC 结构加固 RC梁 受弯性能 试验研究 

分 类 号：TU528.58[建筑科学—建筑技术科学]