Joint identification of elastic modulus and cross-sectional area for truss structures via gradient regularization method

For a truss structure, the most common damage manifestation is the reduction of elastic modulus due to the degradation of material properties and the reduction of effective cross-sectional area caused by corrosion, etc. Based on the single parameter identification gradient regularization method (GRM), this paper proposes an elastic modulus and cross-sectional area dual-parameter joint identification method. Firstly, a mathematical and physical model for dual-parameter joint identification is constructed, followed by the derivation of the solution formula for dual-parameter identification based on GRM and the development of a general finite element solution program using MATLAB. A series of numerical simulation experiments are conducted. The results of which show that the identification results under different working conditions are in good agreement with the actual design parameters, and the solution precision can be as low as 10-7 with less than 10 iterations, and the error is below 4% under 12% measurement noise. The method is further applied to a steel truss experimental model, the results of which furtherly demonstrate the high accuracy and robustness of the method.