Auxiliary Decision-making Method for Cable-stayed Bridge Construction Based on Surrogate Model Under Uncertain Disturbance
Under the influence of uncertain factors during construction of cable-stayed bridges,unsafe issues such as bearing detachment may occur.In view of the construction auxiliary decision-making problem under the influence of such uncertainty factors,this paper proposes a reliability optimization method based on the surrogate model,which reduces the risk of the void of the auxiliary pier support by adjusting the thickness of the deck pavement in the second stage load.First of all,in view of the problem of bearing detachment in the process of system transformation of a steel box cable-stayed bridge constructed by incremental launching,this paper analyzes its failure mode,establishes a surrogate model corresponding to the limit state of the failure mode,and evaluates the surrogate model with rationality evaluation indicators,which effectively guarantees the analysis accuracy of the surrogate model;Secondly,this paper establishes a reliability analysis method based on the surrogate model,which realizes the identification of key influence parameters through parameter sensitivity analysis;Finally,an optimization method based on surrogate model is established,and NSGA-Ⅱ is used to solve the optimization problem.Taking a double-tower and three-span cable-stayed bridge as an example,the analysis results show that the method proposed in this paper can effectively reduce the probability of hollow failure of the auxiliary pier support,improve structural reliability,and the mechanical properties of the main tower,main girder,and cable-stayed cable do not significantly change before and after optimization.This results prove that the construction auxiliary decision-making method of cable-stayed bridge proposed in this paper can be used to guide actual engineering construction and achieve good results.