Construction Control Of Long-span Continuous Bridge

The constuction of continuous girder bridges which adopt cantilever laying method, usually needs a complex process.It will be affected by many certain and uncertain factores. The actual construction state of the bridges might deviate from the state of the theoretical design. In order to guarantee the bridge construction quality and the bridge construction security,make sure the main girder alignment and structure internal force is consistent with the design requirements, The bridge construction control is essential.This article,firstly, Bahe river bridge in Hubei Province Macheng to Xishui section of Daqing to Guangzhou highway as the project background,elaborates the basic principle,the actual content and the basic principle of construction control technologies of the long span prestressed concrete continuous beam bridge.It proposes the correct construction control plan which fit for this bridge.It also uses large-scale computation software MIDAS/Civil to carry on the simulation analysis to the Bahe river bridge main span construction process, and introduces the modelling step in detail.It Effectively grasps the stress and the displacement condition of each essential construction stage during the construction process, and provides the reliable data for the construction control work.Secondly, this article discusses the alignment error analysis during the constuction control process emphatically. It takes calculation and comparison in seven ways which influence the alignment of the main bridge. During the construction control process, it uses the GM (1,1) model to make the science forecast for each segment camber's adjustment value, and obtains the precisely elevation of each setting up template.Before the entire bridge closure, it contrastive analysis and summarizes the spot data and calculated value.From the analysis conclusion, this bridge's construction control plan is practical and feasible, and has made the good progress.Finally,it introduces the stress sensor's choice and the arrangement of the Bahe river bridge main span construction process. This article discusses process stress error sources during the pontic construction process, which include steel string strain gauge's installment, zero alignment own factor influence, as well as concretes elasticity coefficient, concretes strain lag, temperature and other external factors' influence,and proposes the plan of stress amends.It makes contrastive analysis between the measured stress on the spot and the theoretical value. The analysis conclusion shows that this bridge's construction control plan is practical and feasible, and has made the good progress.