Study On Safety Application Of Construction Monitoring In A Continuous Rigid Frame Bridge In Wushan County

The prestressed concrete continuous rigid frame bridge is widely used in the construction of high grade highway because of its good stress characteristics.However,the construction technology of the continuous rigid frame bridge is complicated,and the construction process is affected by many factors.Changes in external conditions or human factors will bring unpredictable risks to bridge construction.If accidents occur in the course of construction,they will cause huge casualties and economic losses,and have extremely bad social impact.In order to ensure the structural safety of the bridge,the linearity and stress of the bridge meet the design requirements,it is extremely important to monitor the construction of the whole process of the bridge construction.In this paper,based on the construction project of a large bridge(main span of 55+100+55m prestressed concrete continuous rigid frame bridge)of Wushan County,the adaptive control method is used to monitor the linearity and stress of the bridge,based on the data and bridges of the bridge site monitoring.A comparative analysis of professional software Midas Civil monitors the alignment and stress of the bridge.In this regard,this article mainly completes the following aspects:(1)Comparing and analyzing the construction monitoring methods for continuous rigid frame bridges,selecting the adaptive control method to monitor the bridge,establishing the construction monitoring system of the bridge,and designing the layout plan for the measurement points of the linear and critical section stress of the bridge.(2)Using the finite element software Midas Civil to simulate the bridge structure,using the forward analysis method to calculate the control elevation and theoretical stress values of the main beam during various construction phases,and analyze the stress changes of the main beam elevation and key sections during the simulation construction period.The bridge girder construction is guided by the model's predicted girder elevation control values and stress theoretical data,and through comparison with the actual site survey data,it is ensured that the vertical elevation of the construction stage and the main beam stress are correctly guided.(3)Based on the bridge stability theory and the correct guidance of the construction model,the stability of bridge piers under the six kinds of operating conditions for the maximum cantilever state of the bridge construction is analyzed,and the main load that affects the maximum cantilever stability is obtained.This article is based on the actual bridge project,through the effective monitoring of the bridge,it ensures the final smooth closure of the bridge.The linear and linear design of the bridge is in good agreement,the elevation of the bridge and the stress meet the requirements of the design.Finally,the stability analysis of the bridgeundefineds maximum cantilever state shows that:(1)the largest cantilever of the P1 pier under each working condition The stability of the state is more than 5,and the stability of the structure satisfies the construction requirements;secondly,the axial stress of the pier top is the main factor affecting the buckling critical force of the pier,and the bending moment of the pier will not affect the critical buckling force of the pier;the construction random load and the construction casting error will not affect the axial stress of the pier top,but it will affect the pierundefineds axial stress.Bridge bending moment and bridge cantilever end displacement;bridge construction monitoring should control the bridge construction error and construction random load to avoid the adverse effect on bridge construction;3.The working state of the hanging basket will not cause buckling instability of the pier,but the hanging basket shedding will increase the axial stress of the pier leading to the larger displacement of the cantilever end and will change the bridge.The bending moment and internal force state of the pier should avoid the falling of the hanging basket during the construction of the bridge.(4)the longitudinal and horizontal wind load on the bridge structure is less stable,but it will affect the pier bending moment.Through the analysis and Research on the stability of the pier through various load combination conditions,the safety of the bridge structure is further ensured.Through the practical bridge engineering,the bridge structure is further ensured.The process of construction monitoring and analysis of the results of the construction of the continuous rigid frame bridge in the construction of the stress and line features are fully grasped,the research results can provide a certain reference for the same type of bridge construction monitoring.