Method for Choosing the Optimal Resource in Back-Analysis for Multiple Material Parameters of a Dam and Its Foundation

On the basis of observed data and numerical calculations of dam structural responses, the back-analysis approach is usually used to determine the material parameters of a dam and its foundation. The reasonableness of the obtained result is related to the chosen structural responses and their observations and calculations. To advance the accuracy and efficiency of a back-analysis, some methods need to be adopted to implement the optimal selection for the preceding resource. The criterion of optimal selection is presented. The parameter sensitivity is taken as a key index of optimal selection. The uniform design method is combined with an artificial neural network and support vector machine to build the mapping relationship between multiple material parameters and dam structural responses at different positions. According to the preceding mapping relationship, models are proposed to calculate the sensitivity of a structural response on the material parameter. The parameter sensitivity-based method choosing the optimal resource is developed. One actual concrete gravity dam is taken as an example. The proposed method is used to implement the optimal selection of a back-analysis resource of an elastic modulus on a dam body and a deformation modulus on a dam foundation. The accuracy and efficiency of the optimal resource-based back-analysis is verified.