上跨石津干渠钢桁梁施工技术研究

顶推施工技术是桥梁建设中常见的施工技术之一,它可以有效地解决新建桥梁跨越既有沟渠、线路等复杂的施工环境问题。石家庄市复兴大街市政化改造工程中涉及到一联跨越石津干渠的钢桁梁施工项目,具有一定的施工难度,以该项目为背景进行顶推施工关键技术研究。该文重点阐述钢桁梁拼装与顶推的施工流程,以及施工过程中的相关注意事项,重点对顶推过程中的导梁及成桥后的钢桁梁进行施工过程仿真分析。分析结果表明,顶推过程中,钢导梁的最大应力σ=144.7 MPa,最大变形u=206.7 mm;成桥后钢桁梁的最大拉压轴向应力均发生在主桁架上,大小分别为σ拉=187.6 MPa、σ压=199.9 MPa,在恒载、活载作用下桥面系的位移分别为u恒=55.2 mm、u活=25.6 mm。以上均满足相关规范要求,为类似施工项目提供参考和借鉴。

Jacking construction technology is one of the common construction technologies in bridge construction,which can effectively solve the complex construction environment problems of newly-built bridges crossing existing ditches and lines.The construction project of steel truss beam crossing Shijin Main Canal is involved in the urbanization transformation project of Fuxing Street in Shijiazhuang City,which has a certain degree of construction difficulty.This paper focuses on the construction process of steel truss beam assembly and pushing,as well as the relevant matters needing attention in the construction process,and focuses on the simulation analysis of the construction process of the guide beam in the pushing process and the steel truss beam after the completion of the bridge.The analysis results show that in the process of jacking,the maximum stress of steel guide beam isσ=144.7 MPa and the maximum deformation is u=206.7 mm.After the completion of the bridge,the maximum axial stress of the steel truss girder occurs on the main truss,and the magnitude isσtension=187.6 MPa andσpressure=199.9 MPa respectively.Under the action of dead load and live load,the displacement of the bridge deck system is u constant=55.2 mm and u active=25.6 mm respectively.The above all meet the requirements of relevant codes and provide reference for similar construction projects.