Study On Construction Control And Key Technology Of Extradosed Cable-Stayed Bridge

The extradosed cable-stayed bridge has developed rapidly in the last twenty years because it has a reasonable structure system.It is forced by the main beam,cable and bridge tower,and has good economy and adaptability.It has a strong competitiveness on the span level of 100m~200m.With the increasing attention of the extradosed cablestayed bridge both at home and abroad,the line type control and structural safety of the construction process are also concerned.Therefore,the study on the construction control of the extradosed cable-stayed bridge has an important practical significance for promoting the overall development.In this dissertation,based on the construction of the extradosed cable-stayed bridge,the bridge and construction stages,the stress and deformation characteristics of linear construction process factors influencing stress control and construction error is analyzed and studied in detail.1.Combined with modern bridge construction technology and modern control theory,the main control contents of construction control for extradosed cable-stayed bridge are introduced in detail;The control method of construction process is described in detail,;the simulation analysis method of construction process in control method is summarized.At the same time,the main influencing factors of construction control and the adjustment theory of construction error are briefly introduced.2.Combined with the actual engineering background,the finite element analysis model of the full bridge is established by using the bridge structure analysis software;The stress and deformation state of the bridge is analyzed,and the design of the bridge is checked with different software;the cantilever construction method of bridge is simulated,and the stress characteristics of the bridge structure in each construction stage are calculated and analyzed,and the safety of the construction process is verified.The key sections and key steps of the construction control are analyzed in detail as the theoretical basis for the construction control.3.According to the actual situation of extradosed cable-stayed bridge,the control theory of the bridge were carried out using the effective control of construction;the setting of the prearch of the bridge and the method of determining the elevation of the vertical die are introduced in detail;the result of line type control in the main construction stage of the bridge is introduced,and the line type in the following construction stage is predicted;the stress control results of the main control section of the bridge are introduced,and the control results of the initial tension of the cable-stayed cable are introduced.Through the control results,we can see that the main girder alignment of the bridge meets the design requirements,the critical section stress is in the safe range,and the initial tension error of the cable is in the controllable range.4.The main factors that affect the construction control are summed up in the light of the data collected from the actual project and the data of the structural calculation.The sensitivity of the main influence parameters of the construction control is analyzed,and the main design parameters are corrected.Combined with the previous construction experience and error analysis,the key factors and practical suggestions are put forward for the construction process.5.In the construction control of the extradosed cable-stayed bridge,the key techniques,such as the calculation of the closing thrust and the adjustment of the cable force,are studied.Different calculation schemes of top thrust are proposed,compared and analyzed.The calculation method of the actual bridge state target cable force is studied.Combined with the non stress state method,the operation method of the actual cable adjustment is put forward.