Real-time hybrid simulation for structural control performance assessment

Abstract

Real-time hybrid simulation is an attractive method to evaluate the response of structures under earthquake loads. The method is a variation of the pseudodynamic testing technique in which the experiment is executed in real time, thus allowing investigation of structural systems with rate-dependent components. Real-time hybrid simulation is challenging because it requires performance of all calculations, application of displacements, and acquisition of measured forces, within a very small increment of time. Furthermore, unless appropriate compensation for actuator dynamics is implemented, stability problems are likely to occur during the experiment. This paper presents an approach for real-time hybrid simulation in which compensation for actuator dynamics is implemented using a model-based feedforward compensator. The method is used to evaluate the response of a semi-active control of a structure employing an MR damper. Experimental results show good agreement with the predicted responses, demonstrating the effectiveness of the method for structural control performance assessment.

A shaking table real-time substructure experiment of an equipment–structure–soil interaction system

“…Due to complex dynamic characteristics of the shaking table, the pure-delay model cannot meet the requirements of control compensation. Inverse dynamic compensation strategy 28 can eliminate magnitude and phase errors of the shaking table after obtaining an accurate mathematical model representing its dynamic characteristics, as shown in Figure 6. As shown in the figure, input r and output y are given as y = C(s)G(st)r, whereas the controller C(s) equals the inverse dynamic model of shaking table G(st).…”

Effects of Equipment-Structure-Soil Interaction on Seismic Response of Equipment and Structure via Real-Time Dynamic Substructuring Shaking Table Testing

“…Insofar as a shaking table has a complex dynamic behavior, its reduction to a timedelay system will not completely compensate the errors in the loading system. In the inverse dynamics compensation method of the shaking table [25], the relationship between the input signal and output signal can be expressed as = ( ) ( ) . If an accurate mathematical model of the shaking table is constructed and an inverse solution is derived from it, then ( ) ( ) = 1, and the amplitude and phase errors in the loading system would be eliminated.…”

Real-Time Error Correction in Fast Pseudodynamic Testing: A Numerical Study

“…Due to these interactions, a time delay exists between when the displacement is commanded and when the specimen actually reaching the target displacement [7]. In a PSD test, the numerical integration algorithm calculates the time history response using the measured restoring forces from the test specimen and commanded (computed) displacements.…”