Numerical simulation of ambient vibration tests: A case study

The paper introduces a numerical procedure to simulate an ambient excitation of structures. The procedure is applied to a case study of a RC framed building that was studied through a process of structural identification by a dynamic test in situ and a model updating. After this first step the numerical model was used to analyse the response of the structure to different excitations in order to simulate the effect of ambient vibrations and the data collected during a monitoring process; the aim is to reproduce the identification procedure exciting the numerical model. The choice of the signal that can simulate the ambient vibrations used in the experimental dynamic tests is a critical point, therefore the dynamic structural response under different inputs was investigated. The numerical dynamic identification procedure was utilized to highlight the ability of different type of signals to excite only some of the global natural vibration frequencies of the structures, so that the dynamic behaviour of the structure can be obtained by the superposition of the results.