Research On The Key Technology Of The Construction Monitoring Of A Continuous Box Girder Bridge

A municipal composite bridge in Zhengzhou is located in the intersection of the main road of the city,and the traffic volume is very high,the bridge was required to meet the needs of the traffic and be coordinated with the surroundings within a limited time under the environment of High social attention and heavy task.M main span bridge,the longest and highest part of the composite bridge,is a prestressed continuous concrete bridge with simple-box double-cell and two parallel style.The M main span bridge was designed of using hanging basket,and the high error of the two bridges should be kept within the plus or minus 30 mm.The composite bridge was required to be completed ahead of time by the landlords and the community,so the special processes,eight hanging baskets were used at the same time,and rebar binding synchronized with the concrete,were adopted for the first time during the construction process.The safety,quality of the construction process and the linear elevation respective were considered in Conventional technology,more than that,the problems of accelerating the mutual calibration of the two bridges and shortening the project period were introduced into the new technology.Focusing on the problems,the following work is carried on in this paper with this bridge as an example.1.The construction method,monitoring method,finite element modeling analysis and other methods of the construction method of continuous girder bridge of prestressed concrete home and aboard are analyzed,it provides experience and data basis for the smooth construction.2.The bridge finite element analysis is carried out,and the internal force and deformation of the cantilever beam are obtained accurately by MIDAS software,which provides data supports,safety evaluations,etc.of vertical mold control,and pre-arching control,etc.in the construction process.3.The adaptive control method was introduced,it can undertake parameter sensitivity analysis,identification of primary parameters and secondary parameters,then adjust the monitoring data of construction process.Adopting adaptive control method reduces the accumulation of parameter errors and ensures the smooth convergence of the bridge.4.By monitoring linear and stress,the bridge height and the line shape,the bridge structure and the concrete force are controlled in a reasonable range,and the construction period structure is safe and manageable.It ensures that the internal and structural elements of the bridge meet the design requirements and lay a good foundation for the smooth closing of the bridge.5.The characteristics of the internal force and the linear adjustment of the bridge beam in the construction process of double width bridge when hanging baskets extending were studied.The comparison,analysis and adjustment of the measured values were compared with the calculated values to control the bridge's linear and stress change effectively.It provides relevant construction parameters to meet the design and specification requirements,and it can provide relevant construction parameters for similar bridges,too.