Effective Force Testing: A Method of Seismic Simulation for Structural Testing

Abstract

This paper presents a test method for real-time earthquake simulation studies of large scale test structures. The method, effective force testing (EFT), is based on a force control algorithm. For systems that can be modeled as a series of lumped masses (e.g., frame structures where masses are assumed lumped at the floor levels), the EFT forces are known a priori for any acceleration record. As opposed to the pseudodynamic test method (a displacement-based control procedure), there is no computational time required for the EFT method in determining the required force signal; it is known prior to the test once the structural mass and ground acceleration record to be simulated are determined. Research has been conducted on a single-degree-of-freedom system at the University of Minnesota to investigate the potential of the EFT method. A direct application of the method was found ineffective because the actuator was unable to apply force at the natural frequency of the structure owing to actuator/control/struc...