Research On Rotary Slip Construction Control Technology Of Long-span Steel Bridge With Full-bolted Connections

The common construction methods of long-span steel bridges include traversing construction method,cantilever construction method,floating construction method and rotary construction method.When the bridge spans existing line and the construction site is limited,rotary construction method or thrusting slip method is often used.The development and research status of bridge rotation construction technology and bridge construction monitoring technology at home and abroad are summarized.On this basis,the selection method of monitoring parameters for rotating slip construction monitoring of steel truss bridge is analyzed,the applicable conditions of various testing methods are pointed out,and the layout method of monitoring measuring points and the setting method of monitoring parameters control index are expounded.In the aspect of missing data processing of steel structure construction monitoring,the missing data processing methods in the field of statistics are reviewed,the missing characteristics of construction monitoring data are analyzed.On basis of the above research,two methods for repairing missing monitoring data are put forward.The layout theory of monitoring points and the theory of missing data processing are applied to a 96 m span steel truss bridge rotary slip construction project.Finite element method is used to simulate the whole construction process.The stress state of steel bridge and temporary structure in each construction step is analyzed to provide theoretical reference value for monitoring.At the same time,the influence of special variables such as the height difference between unloading points and the start/brake acceleration of hydraulic pushing equipment is analyzed.Through the above simulation analysis,the relevant control indexes are put forward.Real-time monitoring of stress level and deformation value in key areas is carried out.The monitoring results show that the measured values are in good agreement with the theoretical calculation values.Stress state of the temporary structure is under control,and the steel bridge line type meets the design requirements.The results of monitoring data processing show that when the number missing data is small,the relative error of most missing data repaired by the two methods is less than 10%,which basically meets the engineering requirements.