Experiments #2, preliminary tests on gravity frame test specimen

Data from a set of four preliminary tests (PT02 test series) conducted prior to Hybrid Simulations 2 on the gravity frame and a cyclic test (Cyclic02 test) conducted at the end of the test series is provided here. The first two preliminary tests, namely, PT02-01 and PT02-02, were conducted first to quantify the flexibility of the support boundary conditions of the Physical Sub-Structure #2. In these tests, the physical sub-structure remained elastic with a maximum inter-story drift ratio at the first story limited to 0.3%. For the hybrid simulations, the numerical sub-structure of the gravity frame was updated with the experimentally-measured flexible support conditions. The preliminary test PT02-03, conducted to verify the transfer of displacement and force command vectors as well as the force feedback vector, was stopped due to instability of the controller of the vertical actuators. This test was successfully repeated as PT02-04.