A Real-time Predictive Study on the Deformation of Incremental Launching Construction of Steel Box Girder Based on Numerical Inverse

In order to obtain a finite element model of steel box girder incremental launching construction that matches the actual structure and to solve the problem of difficult prediction of structural deformation in incremental launching construction, this paper combines the incremental launching construction with the response surface finite element correction technique and proposes a real-time prediction method of steel box girder incremental launching construction deformation based on numerical inversion. The method is applied to the calculation of a steel box girder step incremental launching construction. Firstly, the initial incremental launching construction full working condition finite element model is established, the modulus of elasticity and density of the main girder, guide girder and link truss of the jacked bridge are selected as the parameters to be corrected, the test design is carried out using the central composite design method, and the test sample calculation is quickly carried out in combination with the Python interface in the secondary development interface of ABAQUS software to obtain the response The objective function is constructed by using the Fmincon solver in Matlab to solve for the objective function, and the corrected parameters are substituted into the original model to calculate the structural deformation for the subsequent working conditions. The model is then modified if it exceeds the warning value, and recorded if it does not. The results of the study show that after the four finite element corrections, the calculated values of the subsequent predicted working conditions are very close to the measured results, indicating a good correction effect. Compared with the initial finite element model, the error is significantly reduced, and the error between the corrected response values and the measured values is less than 10%.