Real-time hybrid simulation of 9-story structure with MR damper

The goal of this experiment is to verify the accuracy and stability of the proposed actuator control strategies in a real-time hybrid simulation (RTHS).

A nine-story steel frame benchmark structure is chosen for this RTHS (Ohtori et al. 1994). This structure has 5 bays in NS and EW directions. The first 5 natural frequencies of this structure are 0.443, 1.18, 2.05, 3.09, and 4.27 Hz, with a maximum natural frequency of 63.6 Hz for the 29th mode. Structural files can be found on NEEShub (Dyke et al., 2010).

Structural control provided by MR dampers, added to the structure between the ground story and first story for this study.

In this RTHS, the MR damper is represented by a physical specimen, while the rest of the structure is simulated numerically. The input earthquake investigated is the 1940 El Centro earthquake with a scale factor of 0.5. The CDM is selected for numerical integration with a sampling frequency of 2000 Hz.

The actuator controllers investigated include CDM and BDM feedforward controllers for the average specimen condition both with and without feedback control.

Variations include:
a. CDM controller
b. CDM w/FB controller
c. BDM controller
d. BDM w/FB controller

Ohtori, Y., Christenson, R.E., and Spencer Jr., B.F. (1994), "Benchmark control problems for seismically excited nonlinear buildings." Journal of Engineering Mechanics, 130(4), 366-385.

Shirley Dyke, Anil Kumar Agrawal, Juan M Caicedo, Richard Christenson, Henri P Gavin, Erik A Johnson, Satish Nagarajaiah, Sriram Narasimhan, Billie F. Spencer (2010). "Database for Structural Control and Monitoring Benchmark Problems," Network for Earthquake Engineering Simulation (database), Dataset, DOI:10.4231/D3Q52FC7T