| With the rapid growth of traffic volume,the constant maturity of design theory and the rapid advancement of construction technology,cable-stayed bridges have mushroomed around the world.When the finite element model of the cable-stayed bridge is subjected to force analysis,it is first necessary to provide a set of initial cable forces so that the bridge can meet the basic parameters and performance of the design under the effect of the bridge dead load to achieve a reasonable stress state and geometric linear shape.The traditional cable force adjustment method is a repeated iterative trial process,which is often time-consuming and difficult to converge,and has certain experience.The purpose of this paper is to propose a cable force adjustment method based on the Kriging alternative model.By establishing the corresponding relationship between the initial cable force and the deck configuration,the purpose of calibration cable force can be achieved.This method is fast,accurate,and avoids repeated iterations of finite element iterations.This paper uses a simple numerical example of cable-stayed bridge to verify the feasibility and accuracy of this method.The results show that the Kriging method can greatly improve the efficiency of the results while ensuring the accuracy of the results.Finally,using the Taiping Lake Bridge as the engineering background,the engineering applicability of the method was further verified.The main research work and conclusions of the dissertation include:1.Firstly,the establishment method of Kriging model is introduced,and the concrete steps of Kriging model for cable force adjustment of the finite element model of cable-stayed bridge are given.The finite element model of the numerical example was established.The cable displacement was taken as the input and the vertical displacement of the cable beam joint was used as the output.The uniform design method was used to construct the Kriging surrogate model.The comparison with the traditional zero displacement cable force adjustment method showed that the method was effective.The cable forces can be optimized in a shorter period of time with higher accuracy.2.Based on the design drawings,the initial finite element model of the Taiping Lake Bridge was established,and the cable force sensitivity analysis was performed.The corresponding cable force and other cable forces optimized by the Kriging model were used together as the initial value,and the vertical displacement of the cable beam joint was To control the target,the loop iteration is used to obtain the bridge cable force of the Taiping Lake Bridge.3.The Taiping Lake Bridge has been in service for many years.Based on the data of the health monitoring system,the Taiping Lake Bridge finite element model was corrected using the quadratic response surface method to obtain a benchmark finite element model that can be used as a "simulation" calculation analysis for tuning.The Taiping Lake Bridge was tested for the line and force of the bridge deck.The Kriging method was used to optimize the cable force of the Taiping Lake Bridge based on the benchmark finite element model.The results showed that the cable force optimization results and the measured cable force values were within the allowable range of the project.The obtained bridge surface shape is in good agreement with the measured value. |
