Study On Construction Technology Of Shanghai-kunming High-speed Railway Chahe Rigid Frame Bridge With High-pier And Large-span

The Chahe bridge is one of the rigid frame bridges with high-pier and large-span of between Shanghai-Kunming high-speed railway,which high piers is 103 m high and the main bridge is 344 m three-span continuous rigid frame with 88 m + 168 m + 88 m.Taking Chahe super-bridge as engineering background,the construction technology of rigid-framed bridge with high pier and long-span railway is studied.The main achievements and achievements are as follows:(1)In view of the fact that the construction of the Chahe Bridge is narrow and the large-scale equipment can not be deployed and unfolded,put forward and implementation of the “cable hoisting system and tower crane with construction technology” of the rigid frame bridge with 103 m high piers and three-span continuous rigid frame with 88 m + 168 m + 88 m,to solve the problem of the safety and rapid construction of high-speed railway heavy bridge in the steep valley of southwest mountainous area.(2)According to the characteristics of the steep valley landscape in the southwest mountainous area,it is determined that the main body of Chahe Bridge adopts the cantilever basket perfusion construction,the 0 # section,the cast-in-place construction of side-span cast-in-place section and side-span closed section is carried out by steel pipe bracket method,the hanger is used for the construction of mid-span closed section,and the whole bridge construction project.The construction scheme of the main continuous rigid frame bridge of Chahe Bridge(88 + 168 + 88)is analyzed,and the corresponding scheme is put forward.(3)To establish the finite element model of Chahe bridge by midas civil,according to the analysis results are given the deflections of the girder end(the vertical elevation of the construction basket or the elevation of the beam section)construction control parameters,which provides the control theory data for the linear control and stability evaluation of the bridge construction.(4)To carry out the implementation of Chahe bridge construction monitoring.Through setting up the sensor and elevation measuring point of concrete stress-strain test,testing the numerical value of stress in the process of construction and the changes of the height of cantilever construction;based on the comparison of numerical simulation results.To ensure that the structure of the force and deformation is always in the safe range,the internal force and linear line of the structure conform to the design requirements after the completion of the bridge.