Shake Table Testing Methodology for Multistory Floor Acceleration Simulation Using a Single-Story Test Specimen

This study integrates analytical and experimental research to develop an innovative shake table testing method called Floor Acceleration Simulation Test (FAST). The primary objective of FAST is to produce an essentially elastic response of a single-story test specimen to replicate the floor acceleration time history including higher-mode effects of a target floor in a multistory building experiencing inelastic behavior during an earthquake. The FAST method is well suited for experimental research where the absolute accelerations and the associated inertial forces of the floor diaphragms cannot be simulated by the majority of the conventional test methods. The proposed methodology is based on a transfer function in the frequency domain to compute the required input motion for testing. Considering the physical constraints of a given shake table test facility, guidelines with two response spectra to bracket the natural frequency of the test building are also presented for practical implementation. Experimental validation was carried out on a half-scale, single-story steel building featuring a composite floor slab, utilizing the NHERI@UCSD Large High-Performance Outdoor Shake Table (LHPOST) facility. The results demonstrate the effectiveness of FAST, as both analytical predictions and experimental outcomes confirm its validity. Despite instances of measured floor acceleration amplitude exceeding the target response due to table input motion overshooting in this test program, test results confirmed that the FAST accurately reproduced the intended frequency content, indicative of higher mode effects in the multistory prototype building, in the single-story test building.