Research on Seismic Capacity Values of Bridge Pile Group Foundations Based on a Data-Driven Approach

Rapid assessment of seismic capacity for bridge pile group foundations under seismic loads is critical. This study employs the second-order central difference method to explore seismic capacity sensitivity and identify critical parameters. Subsequently, 1000 Latin hypercube samples were taken for these parameters, and 1000 analytical models were built. The overall displacement ductility is selected as the capacity indicator, and seismic capacity analysis is conducted on the models to obtain a capacity indicator. A BP model was constructed with the critical parameters as inputs and a capacity indicator as outputs to predict capacity values. Then, a regression function between capacity indicators and critical parameters is fitted to establish a capacity value assessment (CVA) model. Finally, capacity indicators are predicted using both the CVA model and the BP model, and the prediction results are compared. Results indicate that the critical parameters are tensile strength of reinforcing steel, cohesion of soil, cross-sectional area of pile, pile spacing, and longitudinal reinforcement ratio. The BP model can effectively predict the capacity indicators. The computational results of the CAV model show good agreement with the predictions from the BP model, demonstrating the reliability of the assessment model. This study provides a novel approach for disaster prediction of bridge pile group foundations.