Load Optimization Method for Fatigue Testing of Large Deformation Structures Based on Stiffness Matching

Abstract

To enhance the efficiency and accuracy of load optimization for fatigue testing of large deformation structures, this paper introduces a novel load optimization method grounded in stiffness matching. The core of this approach is the utilization of displacement response error as the primary optimization objective. It establishes a robust closed-loop framework: “Test State Load Optimization Design Stiffness Model-Based Displacement Response Calculation Displacement Response Error Evaluation.” This comprehensive framework is designed to ensure the precise assessment of structural stiffness and to guarantee that critical displacement responses meet stringent requirements. Initially, simplified linear and non-linear finite element stiffness models of the structure are meticulously con- structed and identified using historical test data. Subsequently, a sophisticated load reconstruction model for large deformation structures is developed. This model integrates theoretical loads into the deflection curve to accurately determine loading point coordinates and force directions, which are crucial for realistic simulation. The efficacy of this method is demonstrated through a case study involving a high-aspect-ratio wing. The results unequivocally show that this method effectively accounts for the complex effects of structural deformation, optimizes both loading coordinates and applied loads, and achieves a remarkable consistency between experimental and theoretical structural responses. This leads to a significant improvement in both precision and efficiency, substantially outperforming conventional load optimization techniques.

Keywords: Large Deformation Structures; Load Optimization; Stiffness Matching; Model Reconstruction; Geometric Non- linearity; Fatigue Testing

Citation

Fahad Abul Kalam. Load Optimization Method for Fatigue Testing of Large Deformation Structures Based on Stiffness Matching. WebLog J Comp Sci Technol. wjcst.2026.f1205. https://doi.org/10.5281/zenodo.20964283