Parameter Identification In The Construction Of Bridge Based On PC-Kriging Surrogate Model

In order to ensure the quality and safety of bridge construction and improve the quality of operation after the completion of bridge,for the problem that the elevation error accumulates constantly in the process of bridge construction because of the difference between actual parameters and design parameters.We proposed a new method called Polynomial-Chaos-based Kriging for parameter identification in the construction of bridge,and the theoretical origin of the method is described in detail.Finally,we studied this method based on the engineering background of Chaozhou bridge.The work presented in this dissertation focus on several aspects of the following:(1)Based on the collection and collation of related researches at home and abroad,the research situation of the theoretical source of PC-Kriging called Kriging and Polynomial Chaos Expansion is introduced in detail.We found that the two methods are mainly used in the field of design optimization and reliability analysis,which have not been used in the field of parameter identification.(2)The basic principle of Kriging method is elaborated in detail.At the same time,the DACE toolbox for establishing Kriging surrogate model is briefly presented.And then a new method for sampling called Number Theoretic Method is introduced.Finally,three numerical examples are used to verify the ability of high accuracy prediction of Kriging surrogate model.It also shows that the sample extracted by the Number Theoretic Method is more reasonable than the traditional Latin Hypercube Sampling.(3)Combined with the research results at home and abroad,we put forward a new method whose principle and algorithm are introduced in detail for identifying parameters in the construction of bridge,and the program of PCE regression function part was written by Matlab,and then we sorted out the flow chart that the PC-Kriging is used to identify the parameters in bridge construction.Finally,the calculation results of five numerical examples indicate that the PC-Kriging performs better than or at least as good as only the Kriging.(4)Based on the engineering background of Chaozhou bridge and the result of sensitivity analysis,the PC-Kriging is used to identify the parameters in the construction of prestressed concrete cable-stayed bridge.The identified results are consistent with the measured data,and the accuracy can meet the needs of engineering,which put forward a new idea of reference for parameter identification.