Study On Construction Control Of The Multi-span Continuous Beam-arch Combination Bridge Based On The Grey System Theory

The develop trend of bridge to span great rivers or bays or other barriers are the larger spanand newer style.Meanwhile the construction methods also tend to diversify.This leads to occursa certain result that the existing construction control theory has not fully applicable to a varietyof bridge construction under new situations.It is especially important to seek bridges controltheory and methods that are truly suitable for the construction of new large-span bridges.In thispaper the study is based on the multi-span continuous beam arch combination bridge that isunder construction.In-depth study of the basis of the existing theories and methods ofconstruction control over, some of the existing methods and theories have made improvementsand improved to make it more in line with modern bridge construction technology and methods.(1) Using software of the finite element to set up the spatial model of bridge，and thenCalculate the deformation and stress state of each stage of construction by forward processanalysis and backward process analysis method.Checked parameter and model based on dataof field measurement, to make sure the control process automatically and dynamically. Bearingfour railway line loads, this bridge with a large span width ratio need to consider the torsionaleffect and the stress distribution of the arch foot in the structural analysis. So the3-D finiteelement model of it with software is established in order to improve the control accuracy. Alsothe beam arch combination bridge Arch foot local stress and deformation have been analyzed,provides a theoretical basis for the subsequent construction monitoring work.(2) It is well-known that a construction phase contains multiple construction process,andeach construction processes are closely interlinked and closely related.So the datas from eachconstruction processes should be associated and correlated,then predict the next stage.But thesingle variable gray GM (1,1) model cannot do it.Therefore a multi-variable GM (1, n) modelhave established through theoretical derivation based on the traditional single-variablemodel.The multi-variable GM (1, n) model can associate and correlate first,then predict.In orderto improve the prediction efficiency the single variable model and multi-varaiable model havebeen programmed by the MATLAB programming language.(3) This paper presents the least-squares curve fitting for stress control. By fitting thecurve variation (increase or decrease trend) for the error analysis of the data, this metod abandonthe traditional method of discrete numerical error analysis by direct way.This method alsoovercome the drawbacks that can not be a comparative analysis due to larger deviations of themeasured values with the theoretical values. To improve the efficiency of processing largeamounts of data, The MATLAB programming language is designed to use.Also let the stresscontrol of bridge construction more operational.(4) Based on the actual engineering background, this article will promote the stree-free status method from the application of cable-stayed bridge and the steel truss bridge to the beamarch combination bridge. Finally, the non stress length of the suspenders and the non stresscurvature of the arch rib have been calculated.(5) The article also studied the combination of girder arch bridge suspender forceoptimization method and optimize the cable force of the suspenders. It is made the entire bridgestructure to achieve the target state in the greatest degree in stress and linear after theconstruction phase and into a bridge.