Research On Error Propagation Law And Adjustment Strategy Of Construction Control For Asymmetric Composite/Hybrid Girder Cable-stayed Bridge

The composite/hybrid girder cable-stayed bridge is favored by bridge engineers,widely used in new large-span bridges,on account of its construction convenience,reasonable loading and batter economy.The applications of traditional construction control research are becoming more and more significantly limited for the composite/hybrid girder cable-stayed bridges.Taking an asymmetric laminated/hybrid girder cable-stayed bridge as engineering background,research on error behavior in construction control of long-span composite/hybrid girder cablestayed bridges is carried out.The main research contents are as follows:1?Based on the stochastic response surface method,the explicit function relationship between input and output of bridge structure is fitted,under the influence of random multiparameters.Through partial derivative method,the sensitivity indices of each parameter in the construction stage are obtained;the contribution of control parameters to bridge structure response variability in different construction stages is quantitatively analyzed;taking a Yangtze river highway bridge as an example,the sensitivity analysis method based on random response surface is used to determine the sensitivity parameters of the critical construction stages of the asymmetric composite/hybrid girder cable-stayed bridge.2?The control parameters which are sensitive to composite girder geometry alignment during the construction are concerned;the qualitative and case analysis of the error formation and change during the construction process are carried out,when there are some errors in the control parameters;with the advance of construction,the geometry alignment error of composite girder front endpoints and the variation and propagation law of the stress of the steel beam and deck are studied;and the actual engineering test data are used for further explaining the error propagation law.3?Based on BP neural network and artificial bee colony algorithm,combined with actual adjustment conditions,the cable force adjustment problem is transformed into the minimum value solving problem;the excellent global optimization speed of artificial bee colony algorithm,and the nonlinear mapping relationship established by BP neural network,are used to solve the optimal cable force adjustment problem;the error adjustment results are evaluated from the perspectives of cable force and geometry alignment.