弯起钢筋及折线束对预应力混凝土工字梁抗剪性能的影响:试验研究  

Effect of Harped Rebars and Harped Prestressed Tendons on Shear Performance of Prestressed Concrete I-girders:An Experimental Study

作　　者：林雪峰 任子夤 郑善辉 宋军 LIN Xuefeng;REN Ziyin;ZHENG Shanhui;SONG Jun(Shandong Expressway Construction Management Group Co.,Ltd.,Jinan 250001,China;Shandong Provincial Institute of Transportation Science,Jinan 250102,China;Jinan Transportation Development Center,Jinan 250303,China;Dept.of Bridge Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]山东高速建设管理集团有限公司,济南250001 [2]山东省交通科学研究院,济南250102 [3]济南市交通运输事业发展中心,济南250303 [4]同济大学桥梁工程系,上海200092

出　　处：《结构工程师》2025年第1期133-138,共6页Structural Engineers

基　　金：山东省交通运输厅科技计划项目(2022B84);山东高速济北公路有限公司技术开发项目(2022SDHSJB-GC-16)。

摘　　要：设计了4个钢筋混凝土(Reinforced Concrete,RC)工字梁试件以及3个预应力混凝土(Prestressed Concrete,PC)工字梁试件,剪跨比均为1.16,研究了腹板配筋率、弯起钢筋、直线预应力束、折线预应力束对预应力混凝土工字梁抗剪性能的影响机理。采用四点加载的方式进行抗剪性能试验,获得了各试件的破坏模式、抗剪承载力及荷载-挠度曲线。结果表明:腹板配箍率降低,RC工字梁的剪切破坏模式可由斜压破坏变为斜拉破坏;弯起钢筋可提高RC工字梁的抗剪刚度和抗剪承载力,且对试件的破坏模式影响较小;预应力束对PC工字梁的抗剪刚度提高效果不显著;直线预应力束与折线预应力束在提高PC工字梁抗剪承载力方面具体不同的作用机理;PC工字梁与具有相同尺寸及普通钢筋的RC工字梁相比,抗剪承载力可高出约40%。Four reinforced concrete(RC)I-girder specimens and three prestressed concrete(PC)I-girder specimens were designed with a shear span-to-depth ratio of 1.16 to investigate the effects of web reinforcement ratio,harped rebars,straight prestressing tendons,and harped prestressing tendons on the shear performance of prestressed concrete I-girders.The shear performance tests were conducted using a four-point loading method,and the failure modes,shear capacity,and load-deflection curves of each specimen were obtained.The results indicate that decreasing the web reinforcement ratio of stirrups can change the shear failure mode of RC I-girders from diagonal compression failure to diagonal tension failure.Harped rebars can enhance the shear stiffness and shear capacity of RC I-girders with minimal impact on the failure mode.Prestressing tendons do not significantly improve the shear stiffness of PC I-girders.Straight and harped prestressing tendons exhibit different mechanisms in enhancing the shear capacity of PC I-girders.Compared to RC I-girders of the same size and ordinary reinforcement,PC I-girders can achieve approximately 40%higher shear bearing capacity.

关 键 词：预应力混凝土工字梁 弯起钢筋 折线束 抗剪性能 试验研究 

分 类 号：TU378.2[建筑科学—结构工程]