Experimental Studies on Real-Time Testing of Structures with Elastomeric Dampers

Real-time pseudodynamic (PSD) and hybrid PSD methods are a means to evaluate structural performance under dynamic loading when a component of a structural system cannot be accurately modeled and is load rate dependent. The real-time PSD and hybrid PSD testing of structures with full-scale elastomeric dampers is presented. A Bode diagram of the complete real-time testing system is used to design a velocity feed forward component that improves the tracking performance of the command displacements by the hydraulic actuator. To evaluate the accuracy of the tests, an on-line error tracking indicator is developed to monitor errors due to actuator lag or lead together with an amplitude indicator to reveal the amplitude errors in actuator measured displacements. The results from the real-time PSD and hybrid PSD tests are presented and evaluated using the error tracking indicators. The stability limits associated with a time delay for the tests are discussed and compared with delays that occurred in the tests.