Soil-Structure Dynamic Interaction under Field-Simulated Ground Motion Tests

To study the soil-structure dynamic interaction, field-simulated ground motion tests of a 15-storey reinforced concrete frame structure are designed and performed. The response records of the structure and ground motion near the foundation are processed and analyzed. The fixed-base natural frequencies and modal damping ratios of the superstructure are determined and compared with the results obtained by the pulsating test. At the fundamental system frequency, the relative roof displacement is almost caused by the rigid-body motion of the foundation. The foundation impedance functions can also be derived from the response data. The test results show an improvement in the accuracy of the amplitude-frequency and phase-frequency characteristic curves and effective reduction in the measurement errors of the phase difference.