连续梁0#块托架预压的设计及应用

Design and Application of Preloading for 0#Block Bracket of Continuous Beam

新建兰州至张掖三四线铁路兰武段下河东特大桥跨连霍高速连续梁0#块施工中,连续梁主墩采用预埋牛腿,在墩身施工完成后在墩身上安装托架搭设0#块施工平台,通过取得弹性变形值,验证托架的安全性、可靠性、消除托架的非弹性变形,结合现场实际工况采用反力法预压,即在承台施工过程中预埋精轧螺纹钢,待墩身强度达到设计强度后安装托架,上下连接采用精轧螺纹钢进行连接预压。反力架法预压主要的设计原则在对反力架结构安全性和适用性,本文结合下河东特大桥跨连霍高速连续梁主墩0#块托架反力法预压施工的实例,介绍了反力法预压的设计及其实践应用的效果。

In the construction of 0#continuous beam of Xiahedong Super-large Bridge across Lianyungang-Khorgos Expressway of Lanzhou-Zhangye No.34 Railway,the main pier of the continuous beam is pre-buried corbel.After the completion of the pier construction,the bracket is installed on the pier to set up the construction platform of 0#block.By obtaining the elastic deformation value,the safety and reliability of the bracket are verified and the inelastic deformation of the bracket is eliminated.Combined with the actual working conditions of the site,the reaction method is used to pre-press,that is,the fine rolled screw steel is pre-buried in the construction process of the cap,the bracket is installed after the strength of the pier reaches the design strength,and the fine rolled screw steel is used to connect the upper and lower connections.The main design principle of the reaction frame preloading method is the safety and applicability of the reaction frame structure.This paper introduces the design of the reaction frame preloading method and the effect of its practical application by combining with the example of the 0#block bracket preloading construction of the main pier of the continuous beam of the Xiahedong Bridge.