Multi-parameter inversion of concrete face rockfill dam using wild horse optimizer and optimal polynomial chaos kriging

Structural parameter inversion is essential for monitoring and assessing the risks of concrete face rockfill dams. Current parameter inversion techniques are, however, often overly complex, computationally demanding, and inefficient, especially when the dam is simulated with a 3D nonlinear finite element method. This study proposes a novel approach combining the Wild Horse Optimizer with Optimal Polynomial Chaos Kriging (WHO_OPCK) to tackle these issues. The method benefits from the low computational cost of optimal polynomial chaos kriging and the fast convergence of the wild horse optimizer. By incorporating statistical uncertainty in input parameters, the method successfully inverts four key constitutive parameters <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>φ</mml:mi> </mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow> <mml:mi>K</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>b</mml:mi> </mml:mrow> </mml:msub> </mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>K</mml:mi> </mml:math> , and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>f</mml:mi> </mml:mrow> </mml:msub> </mml:math> based on displacement data from a complex dam. The approach proves practical and cost-effective in real engineering applications and has culminated in the development of specialized software that streamlines this structural parameter inversion process. Sensitivity analysis using Sobol’ indices further highlights the importance of each parameter at a low computational cost. The study highlights two key advantages of WHO_OPCK: (i) Unlike traditional methods that struggle with complex dams, WHO_OPCK significantly reduces computational costs and handles parameter determination efficiently. (ii) Compared to other surrogate model combinations with WHO, the proposed WHO_OPCK method offers superior accuracy and efficiency. This method establishes a solid foundation for multi-parameter inversion in concrete face rockfill dams.