Using an Improved Response-Surface Method to Enhance the Precision of the Traditional Response Method in Bridges

To improve the precision of traditional response surface methods, an updated response surface method is proposed. Combining the updated response surface method and fmincon algorithm, the accuracy of the finite-element model of a certain prestressed concrete continuous beam bridge is improved using the data of in situ dynamic testing. First, on the basis of specific configurations of a certain prestressed concrete continuous beam bridge, three specific design parameters that need to be updated were preselected. Eigenvalues of 15 samples were calculated using the central composite design method. The response surface method was updated by obtaining the internal relationship between specific design parameters and response eigenvalues. Fifteen response eigenvalues were calculated by finite-element analysis. Using the lsqcurvefit algorithm, undetermined coefficients of the updated response surface model were calculated, and the updated design parameters and response eigenvalues were obtained using the fmincon algorithm from the MATLAB toolbox. Numerical examples show that the updated design parameters and response eigenvalues are reasonable when compared with original parameters. Using the updated response surface method and fmincon algorithm, the numerical model of a prestressed concrete continuous beam bridge was updated effectively.