Construction Monitoring Simulation And Analysis Of Partial Stress Of The Continuous Box Girder Bridge

The Prestressed concrete continuous girder bridges have the characteristics of good mechanical performance, small deformation, less expansion joints, smooth and comfortable when driving, concise and beautiful on modeling, less quantities maintenance and strong earthquake resistant capability. It becomes a kind of the most competitive main bridges. The construction of prestressed concrete continuous box girder bridge uses the method of cantilever casting. It is difficult and complicated in the construction progress. So construction monitoring and control is the important measure to ensure that the design meet the requirements in finished Large span bridge. At the same time, construction monitoring and control is the important link of construction quality and construction safety.Based on the YanShaoHe bridge, the paper mainly completes the following content:(1)Introducing the development of continuous girder bridge and mechanical characteristics, the main content, development status and significance of construction monitoring.(2)Introducing the theory of simulation of continuous box girder construction, it mainly including the simulation calculation method and the finite element theory.(3)Under the construction procedures of YanShaoHe, using the finite element software Midas/civil to establish the construction simulation model of full-bridge, comparing the displacement, stress and internal force of maximum cantilever with finished state.(4)Introducing the bridge detection scheme of construction site (including linear and internal force), the elevation changes of maximum cantilever and finished state are given on the line surveillance, several key section’s control stress are given on the stress monitoring. comparing the differences between the measured values and the theoretical value.(5)Using The finite element software ABAQUS to establish0#block partial entity model, through the analysis of the maximum cantilever state and finished state in the roof, the backplane, the webs and the horizontal septum board, and find out the large stress and stress concentrated parts that may appear cracks.The analysis showed that finite element analysis of the construction process by using Midas/civil played a role of reference and guidance to the construction monitoring, validated the measured values by construction monitoring to be in line with the theoretical value basically. The results derived from the analysis of0#block by using ABAQUS showed that varying degrees of tensile stress appeared in the junction between the top and bottom flanges and the diaphragm as well as the joint of the top flange and the webs. Correspondingly it is prone to crack in those parts of the box girder. Measures should be taken to prevent that during the construction.