Theoretical And Practical Study Of Construction Control For Zhaoyuan Songhua River Extra-long Span Bridge

With the rapid development of China's highway and city traffic ,and thedevelopment of modern structure theory ,higher intension of material computertechnology and construction methods,the span of modern bridge become more andmore longer and the structure is becoming slighter and more dexterous. As aresult ,it makes the construction become more difficult.With its good mechanicalbehavior and good load-bearing ability ,consruction rapidness ,convenient forsegmental constuction using the cantilever technique,continuous beam bridgeoccupies the competitive position in modern long-span bridges.The prestressed concrete continuous beam bridge adopts the economical andreasonable segmental construction technique(cantilever installation and cantilevermold).During the process of the balanced cantilever construction ,the bridgestructure is influenced by various factors,such as shrinkage,creep and temperaturechange of concrete,consruction error,survey error,and so on.Such factors result inthe complex change of the internal forces and displacements in the bridge.It isnecessary to execute construction control effectively for bridge'sconstruction,ensuring of smooth closing-join at mid-span,meeting the need ofdesign and keeping the ideal alignment after closing join.In this thesis ,we base on the consruction control and monitor project ofZhaoYan SongHua river bridge.In order to ensure the consistency of practicalalignment of structure and ideal alignment,deflection and internal force winthin theallowable limit, we adopt reasonable finite element computation to simulate theconstruction process in view of the practical construction of long-span continuousbeam bridge.The concept of engineering cybernetics is applied.The constructioncontrol is regarded as stochastic optimal control.Accordingly the mathematicalmodel,the physical model is established.On the basis of the deterministic optimalcontrol,we control the construction by means of the Kalman's filtering method.Atthe same time ,it is provided for adjusting control in different constructionstage,which achieve the optimal control and come to the conclusion.All these canprovide reference and foundation for carrying out the effective control in theproject.The first chapter of the thesis gives a historical retrospect to the developmentof continuous beam bridges,and a detailed account of the balanced cantileverconstruction technique ,and analyze the importance of construction control tocontinuous beam bridges from the begin to post-periodmontoring.Then,introduce the recent research at domestic and abroad,and expositesthe necessity and significance of the study in this paper: First,to analyze the influence of the factors come from the constructionprocedure on the bridge structure internal forces and line form,for the accumulationof experiences to guide construction control in the same type of bridge. Second,to creat reasonable finite element model in order to simulate theconstruction process and compare the internal force and precamber fromprogressive and retrogressive analysis to the data conveyed. Third, to control the construction by means of the Kalman's filtering methodand study the application of the control's theory in the continuous beam bridge'sconstuction. The task of bridge construction control is to monitor and control the process ofthe bridge , In order to ensure the consistency of practical alignment of structureand ideal alignment,deflection and internal force winthin the allowable limit andobserve the specification.Therefore,in the second chapter we discuss the maincontents,methods,and the influence factors of construction control. To make auseful construction control,we should completely understand the factors andestablish the control's operation scheme on account of these.At sametime,according to the status that the finished part of continuous beam bridge cannot be adjusted,the predication control method is credible. To the purpose of construction control,we must adopt reasonable theoryanalysis and computation method to attain the ideal staus of force and transform inevery stage of construction.Then,we can control the structure status of eachconstruction stage,and keep the ideal force and alignment after closing join to meetthe need of design.In the third chapter of the thesis,we discuss the computationprinciple ,structural analysis method and computation method.Then explain what isFinite element simulation.We put an emphasis on explaining the finite elementmethod used on Zhao Yuan Song Hua River BRIDGE construction control. Bycomplying with progressive analysis and retrogressive analysis,we get the idealstatus in every stage of construction.Part of the computation result are in theappendix. Chapter four and five are the kern parts of the thesis.Since the comprehensivedisturb of the design parameter error margin( material characteristic, cut to face thecharacteristic and permit heavy etc.), construction error margin, convey error...