Cable Saddle Pre-partial Construction Of Steel-concrete Composite Beam Suspension Bridge Construction Control Technology

According to the structure characteristics and development of suspension bridge, at present, the main method used widely both at home and abroad for suspension bridge's construction and designing is setting the pre-displacement of main saddle to balance the horizontal force of middle-span main cable and ensure the tower's tensile stress safety during construction, as well as incremental launching middle-span saddle stage by stage based on the tower's tensile and non-balanced force of main cable. The thesis aims at the characteristics of the suspension bridge built by the non-pre-bias of cable-addle and proposes a new method, which has never been used in suspension bridge construction in China. That is: at the time of the saddle installation, the main saddle and the center of tower pole should be fixed firmly and then the structure tensile should be adjusted by the tensile force of cable strands, as well as, the steel-concrete overlapping beam bridge decking system is first used for suspension bridge construction in China. From the angle of simulating analysis on suspension bridge construction, the thesis put forwards a method for setting up a space computing model, which can describe accurately the construction process of the steel-concrete overlapping beam suspension bridge structure built by the non-pre-bias of cable-addle, also simulating analyze the construction process and completion state of the steel-concrete overlapping beam suspension bridge built by the non-pre-bias of cable-addle; combining with the research results of model wind tunnel test on the main beam of Lanchangjiang steel-concrete overlapping stiffening girder suspension bridge built by the non-pre-bias of cable-addle in Xiangyun-Linchang Highway of Yunnan,. Based on the control analysis of anti-wind stability carried out, the construction control of the steel-concrete overlapping beam suspension bridge built by the non-pre-bias of cable-addle has been studied thoroughly, particularly the detailed analysis has been made on the factors, errors, parametric identification which affect the construction control of suspension bridge and also on the construction control of the slant tower rectified by tensile force of cable strands of suspension bridge built by the non-pre-bias of cable-addle. Also, the thesis explores the methods for construction supervision and control analysis of this kind suspension bridge. Main contents presented in the thesis are as follows:1. How to adjust the difference between the structure analysis and designing of suspension and its actual construction? How to analyze the errors and parameters between them and the factors affecting the construction control of suspension bridge? Put forward an analysis and resolve proposal.2. Set up a space computing model fit to simulating analysis and construction control for suspension bridge built by the non-pre-bias of cable-addle. The model set up can fully describe the structure forms, load and boundary condition of each construction stage, and the internal force and deformation of each construction stage can also be calculated accurately when adding the actual computing parameters.3. Study on the finite displacement theory and analytical theory applied to this kind of suspension bridge construction control calculation. Afterward, give new ideas on construction control calculation by means of comparing the different construction methods. Key studies are given to the mechanics characteristics of main cable and selecting and correcting structure calculation model including whole bridge structure calculation model, cable unit treatment, forward and backward calculation, tensile force of cable strands and its control analysis and tensile process simulating etc.4. By comparing with the construction method of pre-displacement of cable saddle, definite the corresponding calculation methods for suspender state and its geometric of the suspender. Study on catwalk, geometric construction control of main cable and temperature control.5. Combining with the research result of model wind tunnel test on the main beam of Lanchangjiang steel-concrete overlapping stiffening girder suspension bridge built by the non-pre-bias of cable-addle on Xiangyun-Linchang Highway of Yunnan, the key analysis are given to wind location characteristics of actual bridge location, structure dynamic characteristics, whole bridge static wind stability, structure wind-load internal force, completion state of bridge and structure anti-wind stability during construction.6. Key study on construction control of slant tower rectified by tensile force of cable strands, the reasonable control value of tensile force of cable strands under high temperature, time periods, amount and force of tensile of cable strands and tensile force supervision.