Construction Monitoring Of Long Span Curved Steel Truss Stiffening Continuous Beam Bridge

In the construction process of long-span bridges,since the design is a set parameter,the parameters in the actual construction are discrete,and the actual values are deviated from the design calculation,which leads to deviations in the deflection and stress of the actual structure.Therefore,construction monitoring is required.To ensure that the line shape and force meet the requirements.In this paper,the cross-Ningluo high-speed curved steel reinforced continuous beam bridge is taken as the engineering background.At the same time,combined with the development status and characteristics of the steel-concrete composite structure,the construction monitoring of the bridge is studied and implemented.The main work contents are as follows:(1)The construction monitoring of the continuous steel beam bridge of the curved steel truss was determined,and three structural analysis methods in the bridge construction process were introduced.(2)According to the design parameters and formal analysis method,the full bridge simulation analysis model was established by using Midas/Civil 2015 finite element software.Based on the model,the installation sequence of steel truss was determined,and the deflection of each construction condition of the structure was extracted.This predicts the vertical model elevation of each segment under each operating condition.(3)Using the finite element model,the sensitivity analysis of main beam weight,main beam stiffness,prestressed tensile control stress,construction temporary load,temperature and concrete shrinkage and creep is carried out.The deflection of the mid-span is taken as the monitoring target,and the influence degree of the parameter on the deflection is judged.In order to more accurately carry out the error analysis of construction monitoring and guide the construction.(4)According to the monitoring plan and on-site implementation,the monitoring process was determined,and the measurement points of the line shape and stress of the main beam and the steel truss were arranged.The measured values and theoretical values of the line shape and the critical section of the bridge main structure were compared and analyzed.The comparative analysis shows that the numerical values of the two are in good agreement,which meets the requirements of design and specification,achieving the purpose of construction monitoring.