不同加载速率下钢筋与混凝土间粘结性能试验  

Experiments on Bond Behavior Between Steel Bar and Concrete Under Different Loading Rates

作　　者：张伟平[1] 罗丹羽[1] 陈辉[1] 顾祥林[1] 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《中国公路学报》2014年第12期58-64,共7页China Journal of Highway and Transport

基　　金：国家高技术研究发展计划("八六三"计划)项目(2012AA050903)

摘　　要：为探索不同加载速率下变形钢筋和混凝土之间的粘结性能,通过37个试件的偏心拉拔试验,实时采集加载过程中的粘结-滑移关系数据,分析了加载速率、保护层厚度、钢筋位置、箍筋和粘结长度等因素对破坏形态、粘结强度及相对滑移的影响。研究结果表明:随着加载速率的增大,混凝土抗拉强度提高且混凝土径向裂缝发展滞后,试件由混凝土劈裂破坏向钢筋拔出破坏转变,劈裂破坏试件的粘结强度提高;在相同加载速率下,随着保护层厚度的增大,试件也会由混凝土劈裂破坏向钢筋拔出破坏转变;箍筋的配置对破坏形态影响不大,但能提高粘结强度,减小峰值滑移量。Thirty-seven eccentric pullout tests under different loading rates were conducted, and load-slip relationship was recorded to investigate the influences of loading rate, concrete cover thickness, reinforcement position, stirrup and bond length on bond behavior between deformed steel bar and concrete. The results show that with the increasing loading rate, the tensile strength is increased, the longitudinal cracking is delayed and the specimens fail from splitting of concrete cover to pullout of steel bars. The average bond strength of the splitting specimens is increased significantly. For specimens under the same loading rate, specimens with thicker concrete cover tend to fail by the pullout of steel bars rather than cover splitting. Little influence of the presence of stirrups is found on failure mode, but the average bond strength is increased and the peak slip is decreased.

关 键 词：桥梁工程 钢筋混凝土 偏心拉拔试验 粘结性能 加载速率 

分 类 号：U441.4[建筑科学—桥梁与隧道工程]