Hybrid Test #2 of the seismic response of a steel gravity frame

Half-scale hybrid tests of a 4-story steel moment frame building including the gravity load resisting system. The physical substructures include a subassembly of the gravity-resisting frame constructed with the composite concrete slab. The one and one-half story physical substructures included additional dead load on the slab at the first story level with the vertical load from the upper stories accounting for overturning forces applied through force controlled actuators. The lateral loading on the frame was applied through displacement controlled actuators commanded by the hybrid simulation algorithm. The mathematical substructures were developed using the Open System for Earthquake Engineering Simulation (OpenSees) and coupled with the Open Source Framework for Experimental Setup and Control (OpenFresco) to integrate the laboratory hardware for the hybrid simulation.