Generalized‐α methods for seismic structural testing

This paper presents novel predictor–corrector time-integration algorithms based on the Generalized-α method to perform pseudo-dynamic tests with substructuring. The implicit Generalized-α algorithm was implemented in a predictor–one corrector form giving rise to the implicit IPC–ρ∞ method, able to avoid expensive iterative corrections in view of high-speed applications. Moreover, the scheme embodies a secant stiffness formula that can closely approximate the actual stiffness of a structure. Also an explicit algorithm endowed with user-controlled dissipation properties, the EPC–ρb method, was implemented. The resulting schemes were tested experimentally both on a two- and on a six-degrees-of-freedom system, using substructuring. The tests indicated that the numerical strategies enhance the fidelity of the pseudo-dynamic test results even in an environment characterized by considerable experimental errors. Moreover, the schemes were tested numerically on severe non-linear substructured multiple-degrees-of-freedom systems reproduced with the Bouc–Wen model, showing the reliability of the seismic tests under these conditions. Copyright © 2004 John Wiley & Sons, Ltd.