混凝土箱梁牛腿裂缝分析及加固技术创新研究与实践  

Research and practice on crack analysis and reinforcement technology innovation of concrete boxgirder corbel

作　　者：毛建平 唐赓 蒙方成 潘栋 Mao Jian-ping;Tang Gen;Meng Fang-cheng;Pan Dong(Guangxi Communications Desgn Group Co.Lid,Nanning 530004,China;Guangxi Traffic Engineering Testing Co.Ltd,Nanning 530004,China;Nanning Survey and Design Institute Co.Ltd of China Railway Siyuan Group,Nanning 530000,China)

机构地区：[1]广西交通设计集团有限公司,广西南宁530004 [2]广西交通工程检测有限公司,广西南宁530004 [3]中铁四院集团南宁勘察设计院有限公司,广西南宁530000

出　　处：《工程抗震与加固改造》2023年第3期166-176,共11页Earthquake Resistant Engineering and Retrofitting

基　　金：国家自然科学基金(51878186、51868007);国家重点研发计划(2019YFC1511103)。

摘　　要：本文详细介绍了某城市立交桥混凝土箱梁牛腿裂缝的专项检测方法,检测结果表明,牛腿裂缝以斜向为主,与底板夹角在27°~45°之间。根据裂缝特征、牛腿结构形式和配筋情况,运用大型有限元软件ANSYS进行数值分析,并在此基础上论述了混凝土牛腿裂缝成因。针对牛腿裂缝引起的结构刚度弱化,影响结构安全问题,综合考虑加固效果、经济性、适用性和耐久性等因素,提出一种钢牛腿置换混凝土牛腿的加固方法。从方法原理、计算分析及施工要点等方面对该方法进行了详细论述,并成功将其运用于实际工程。通过加固后的实桥检测,验证了该加固方法的良好效果,可为同类结构形式桥梁的维修加固提供参考。This paper introduces the special detection method of corbel cracks in a concrete box girder of an urban overpass in detail.The detection results show that the corbel cracks are mainly oblique,and the included angle with the bottom plate is between 27°~45°.According to the crack characteristics,corbel structure and reinforcement,the numerical analysis is carried out by using the large-scale finite element software ANSYS,and on this basis,the causes of concrete corbel cracks are discussed.In view of the weakening of structural stiffness caused by corbel cracks and the impact on structural safety,a reinforcement method of replacing concrete corbel with steel corbel is proposed by comprehensively considering the factors of economy,convenience and scientificity.This method is discussed in detail from the aspects of method principle,calculation analysis and construction key points,and has been successfully applied to practical projects.Through the inspection of the reinforced real bridge,the good effect of the reinforcement method is verified,which can provide a reference for the maintenance and reinforcement of bridges with similar structural forms.

关 键 词：混凝土裂缝 桥梁加固 混凝土牛腿 钢牛腿 

分 类 号：U445.7[建筑科学—桥梁与隧道工程]