The Continuous Steel Truss Girder Cantilever Installation Monitoring Analysis

At present the main structure forms of international and domestic steel bridge are steel box girder structure, long span steel truss structure steel pipe pole or steel box arch structure and steel composite beam structure. Which large steel truss continuous beam bridge structure to the stress is good, the weight is light, meet the higher strength and stiffness requirements, especially the construction of the advantages of mature become across the river bridge.In this paper, based on the background of a continuous steel truss girder bridge in Yangtze River bridge, this paper studies the stress and deformation monitoring of the cantilever erection method. The construction of the long span continuous steel truss girder bridge by using the cantilever erection method. In order to ensure the construction safety of the bridge and to ensure the line and stress of large span steel truss girder bridge meet the design requirements, the safety monitoring of large bridge construction process is a key technology. The purpose of this thesis is the study of long span continuous steel truss beam bridge during the construction process of safety monitoring, and corresponding analysis and research of the process monitoring, the bridge state maximum close to ideal design finished bridge state, and ensure the safety in the process of construction.This paper introduces the development of steel truss girder bridge at home and abroad, and introduces the theory and method of monitoring and control of steel truss bridge. Then, the stress and deformation state of each stage of the construction process of the bridge are analyzed by using the MIDAS/Civil finite element analysis software. The main contents of the finite element analysis include the stress of the main girder of the bridge and the variation of the line shape, the stress and displacement of the semi cantilever bridge of the bridge. Stress measurement of the key parts of the bridge construction process is carried out by using the stress sensor. Through the analysis and comparison of the calculated results and measured values of MIDAS/Civil, the data of the two are basically consistent. In the actual construction process, construction control personnel through the calculation of the comparison between the measurement results and the actual values, to the timely detection of problems, to provide feasible suggestions for the next phase of construction safety, to achieve the purpose of construction monitoring. Thus ensuring the safety of the long-span bridge construction.