"A NON-ITERATIVE DISTRIBUTED SUBSTRUCTURE ONLINE HYBRID TEST METHOD "

Proposed in this paper is a model-based predicting and correcting algorithm (M-PC) which serves as the time integration algorithm for substructure hybrid tests. M-PC adopts the initial stiffness to solve the equation of motion to predict the boundary displacements. Compared with the difference-based predictor, the model-based predictor is characterized by a better accuracy and stability. M-PC is a non-iterative algorithm which is much efficient particularly for the cases with many degrees of freedom associated with substructure boundaries. The M-PC algorithm is first formulated and procedures to implement hybrid test are given. Then a hybrid test framework is developed to realize the interface to two finite element programs, i.e., OpenSEES and ABAQUS. The functions to control servo-hydraulic devices and exchange data via Internet are also integrated into the framework. Finally, a numerical hybrid simulation and physical hybrid test are conducted on a portal moment frame. Both results demonstrate that the M-PC algorithm is able to effectively predict the displacement associated with static boundaries. The responses of the entire structure are reasonable and correctly reproduce the nonlinearities of two substructures.