The Research And Practice Of Construction Monitoring And Control Of Ganzhou Ganjiang Bridge In Changgan Passenger Dedicated Line

The cable-stayed bridge is a structure that uses the cable as a medium to transmit the weight of the main beam and the load of the train to the tower.The main tower bearing capacity of the cable-stayed bridge,the tensile force of the cable,and the bending moment of the main beam are combined.With the increasing of the span of modern cable-stayed bridges,the construction monitoring of cable-stayed bridges is an indispensable part of the construction technology,which is crucial for the quality assurance of bridge structures and the safety and stability during construction.In this paper,the construction and monitoring of hybrid girder cable-stayed bridges is studied and practiced by using the Ganzhou Ganjiang bridge in Changgan Passenger Dedicated Line as an engineering example.(1)Since the theoretical analysis of the model of the cable-stayed bridge is the premise of construction monitoring,the finite element model of the Ganjiang bridge in Ganzhou is firstly constructed using the finite element analysis software to analyze the static and dynamic forces of the bridge and the actual bridge design index.Computational calculations were carried out to obtain the bridge completion phase line type,the critical section stress at each construction phase and the initial tension of the cable.All of them were in accordance with the design values,and the elevations of the elevations of the control cross sections of the concrete side span beam were performed according to the model calculation results.determine(2)Sensitivity analysis was carried out on various parameters of this bridge.The critical sensitivity parameters of the bridge structure were obtained by changing the parameters such as dead weight,elastic modulus,and temperature.The results showed that the bridge has its own weight,tensile force,and concrete.The change of shrinkage and creep has a great influence on the main beam's line type,internal force and cable force.It is a key sensitivity parameter and needs to be emphasized in the construction process and construction monitoring.(3)Conduct construction monitoring for the current construction phase of the bridge,and compare the monitored data with theoretical values.The monitoring and practice results show that the stress and linear theoretical values of the control section of the bridge are close to the actual measured values during the construction phase of the bridge,and the trend of numerical values is basically the same.Within the allowable error range,the calculated value of the cable tension and the design value error are controlled.Less than 5%,in line with monitoring requirements,can guarantee the construction.(4)Finally,the finite element analysis of the heat of hydration was carried out on the massive concrete in the closed section of the tower and the temperature was monitored.The results showed that the temperature change trend was consistent with the finite element calculation and the maximum heat of hydration.The temperature is also within the allowable range of the specification,and it is feasible to set up a cooling pipe scheme.