An enhanced hysteretic force response sensitivity approach is proposed to identify the Iwan model of a bolted joint under the quasi-static cyclic loading. The parameters identification is formulated as a least-squares problem that finds the parameters to minimize the residuals between the measured and predicted hysteretic force. To solve this problem, the sensitivity analysis of hysteretic force response is derived in the discrete form. In doing so, the Heaviside function and smoothing strategy are utilized to overcome the discontinuity of Iwan model and make the response sensitivity accessible. Then, the least-squares problem is linearized by the hysteretic force response sensitivity and solved subsequently by the Tikhonov regularization, in which trust region constraint is employed to enhance the convergence. Numerical simulations and experiment study show that the proposed methodology is accurate and efficient for identifying the Iwan bolted joint models.
展开▼
