Error study of a hybrid testing system of structures through a state-space model

Abstract

Experimental methods such as hybrid or pseudo-dynamic tests are always subjected to experimental errors which effect on the obtained response is important to assess. An analytical linear model formulated on state-space equations has been developed for a multi DoF hybrid testing system including the components of the control and the specimen. For an example of a single DoF steel frame, the parameters of the model have been calibrated through comparison with experimental data of the control system. The model has been used to predict in pseudo-dynamic tests on such specimen the control errors and their consequences in terms of eigenfrequency and damping distortion in the test response. These predictions match with the observed experimental data and allow understanding, for example, the effects on the response of performing the test at different testing speeds or for different parameter configurations of the control algorithm.JRC.G.5-European laboratory for structural assessmen