RESEARCH ON STAGGERED COORDINATION APPLICATION IN HYBRID TEST METHODS

This paper proposed an online hybrid test framework using a static and dynamic separated model scheme, where the equations of motion are solved by the operator-splitting (OS) algorithm and the restoring force is obtained from a static analysis or quasi-static test of substructures. The boundary coordination between the numerical and physical substructure is one of the keys to achieve a hybrid test. This paper proposed a staggered coordination method to coordinate the boundary conditions approximately, in which the displacements of boundaries in the numerical substructure in the current step are measured in the physical substructure in the last step and force analyzed results of the numerical substructure are then exerted on the boundaries of physical substructure for loading. The method was applied to a six floor RC frame retrofitted by double-K BRBs. The error caused by the approximation were confirmed to be negligible through numerical verification. Although this is not an accurate method, it makes hybrid tests easier and more flexible.