摘要
混凝土结合界面是装配式混凝土结构的薄弱环节,套筒灌浆连接混凝土结合界面直剪性能对装配式混凝土结构安全性能至关重要。设计试验研究了钢筋锈蚀对直剪荷载作用下套筒灌浆连接混凝土结合界面的裂缝开展、破坏形态、裂缝宽度-竖向相对滑移关系以及名义剪应力-竖向相对滑移关系的影响,并通过理论分析研究了钢筋锈蚀对结合界面剪应力-竖向相对滑移曲线特征参数与特征系数的影响。研究结果表明:钢筋锈蚀的发展对结合界面直剪加载过程中的裂缝发展刚度具有两个阶段影响,在加载初期,随锈蚀率增长,裂缝发展刚度下降;而在加载后期,随锈蚀率增长,裂缝发展刚度上升。钢筋锈蚀会显著降低套筒灌浆混凝土结合界面的极限剪应力和残余剪应力,当钢筋锈蚀率为3.5%和7.5%时,结合界面的极限剪应力分别下降41%和49%,残余剪应力分别下降约35%和59%。
The concrete interface is the weak link of the precast concrete structures. The direct shear performance of the sleeve grouting concrete interface is significant importance to the safety of the precast concrete structures. The influence of steel bar corrosion on the crack development, failure pattern, relationship of crack width and vertical relative slip, relationship of nominal shear stress and vertical relative slip were examined by the experimental study on the sleeve grouting concrete interface with corroded steel bar under the direct shear load. Meanwhile, the influence of steel bar corrosion on the characteristic parameters and coefficients of the shear stress-vertical relative slip curve was analyzed theoretically. The research results show that the development of steel bar corrosion has two-stage influences on the crack development stiffness of interface during the direct shear loading. At the beginning of loading, the crack development stiffness decreases with the increase of corrosion ratio. However, at the later stage of loading, the crack development stiffness increases with the increase of corrosion ratio. The ultimate shear stress and residual shear stress of the sleeve grouting concrete interface will be significantly reduced by the steel bar corrosion. When the corrosion ratio of the reinforcing steel bar is 3.5% and 7.5%, the ultimate shear strength of interface would decrease by 41% and 49% respectively, and the residual shear stress would decrease by about 35% and 59% respectively.
作者
张雪锋
李丕伟
夏晋
甘润立
金伟良
ZHANG Xuefeng;LI Piwei;XIA Jin;GAN Runli;JIN Weiliang(Hangzhou Urban Highway Co.,Ltd.,Hangzhou 310012,China;Institute of Structural Engineering,Zhejiang University,Hangzhou 310058,China)
出处
《建筑结构》
CSCD
北大核心
2022年第1期120-126,共7页
Building Structure
基金
国家自然科学基金项目(51778566)
浙江省杰出青年科学基金项目(LR21E080003)
国家重点研发计划项目(2016YFC0701406)
浙江省交通投资集团有限公司科技项目(201812)
浙江省自然科学基金重点项目(LZ16E080002)
中央高校基本科研业务费专项(2018FZA4018)。
关键词
套筒灌浆
混凝土结合界面
锈蚀钢筋
直剪性能
装配式混凝土结构
sleeve grouting
concrete interface
corroded steel bar
direct shear performance
precast concrete structure
作者简介
第一作者:张雪锋,学士,正高级工程师,主要从事高速公路建设营运管理工作,Email:171383279@qq.com;通信作者:夏晋,博士,副教授,主要从事海洋环境混凝土结构基础理论工作,Email:xiajin@zju.edu.cn。
