长锚钢筋与混凝土黏结性能的量化分析模型  

Quantitative analysis model of bond performance between long-anchored rebar and concrete

作　　者：高向玲[1] 彭红璐 李杰[1] GAO Xiangling;PENG Honglu;LI Jie(Department of Structural Engineering,Tongji University,Shanghai 200092,China;Central Southern China Electric Power Design Institute Co.,Ltd,China Power Engineering Consulting Group,Wuhan 430071,China)

机构地区：[1]同济大学建筑工程系,上海200092 [2]中国电力工程顾问集团中南电力设计院有限公司,湖北武汉430071

出　　处：《建筑结构学报》2022年第11期266-274,共9页Journal of Building Structures

基　　金：上海市科技委重点创新项目(2017-01-07-00-07-E00006);同济大学双带头人项目(0200219296)。

摘　　要：通过钢筋开槽内贴应变片的黏结滑移梁式试验,研究长锚钢筋屈服前后钢筋的应变及黏结应力分布特征,分析钢筋屈服后发生黏结退化的原因主要是钢筋直径的减小、钢筋的塑性伸长以及接触面的破坏加剧。根据试验结果,构建了在黏结性能中考虑钢筋应变对黏结应力和滑移影响的钢筋应变沿长度方向的分布函数;基于应变分布函数,建立了可量化的长锚钢筋黏结应力-滑移分析模型;基于能量等效原则,提出了钢筋弹性段和屈服段的平均黏结应力的确定方法,以及根据加载端应力和平均黏结应力确定钢筋弹性段的长度。基于此模型,可预测长锚钢筋屈服前弹性段以及屈服后弹性段和塑性段的应变、滑移、黏结应力沿长度方向的分布,并与既有试验结果进行了对比,验证了模型的有效性。该模型可用于罕遇地震作用下混凝土结构的力学性能分析。Beam test was conducted by slotting the reinforcement and sticking the resistance strain gauges.The distribution characteristics of strain and bond stress of the long-anchored steel bar before and after yielding were studied,and the main reason for bond degradation after the yielding of steel bar was the decrease of reinforcement diameter,the plastic elongation of reinforcement and the increasing damage of contact surface.According to the test results,the distribution function of reinforcement strain along the length direction was constructed,and the influence of reinforcement strain on bonding stress and slip was considered.Based on the strain distribution function,the quantitative analysis model of bond stress-slip relationship was established for long-anchoraged rebar.Furthermore,based on the principle of energy equivalence,the average bond stress of the elastic segment and yielding segment was deduced.The length of elastic segment of reinforcement can be determined based on the average bond stress and the stress of the rebar at loading end.Based on this model,the distribution of strain,slip,and bond stress of steel bar of elastic segment before yielding and elastic and plastic segments after yielding along the length direction can be predicted.In addition,the effect of the model was verified by comparing the predicted results with the existing test results.The model can be used for the analysis of mechanical properties of concrete structures under major earthquakes.

关 键 词：长锚钢筋 梁式试验 黏结退化 钢筋屈服 黏结应力-钢筋应变模型 

分 类 号：TU375.103[建筑科学—结构工程]