Effects of separation joints on dynamic characteristics of adjacent structures based on ambient vibration tests

Abstract

Adjacent structures separated by a joint of a building are usually taken as independent ones by design engineers. However, the separation joint may provide some continuity to the real building. This paper studies the effects of the separation joint on the dynamic characteristics of three cases of multi-storey adjacent structures. Both ambient vibration tests and finite element modelling have been carried out for this purpose. Close modes are identified in all three cases by the fast Bayesian FFT method. Dynamic interactions between the adjacent structures via the separation joint are noted. The extent of dynamic interactions depends largely on the technical details of the joint. The natural frequencies and mode shapes identified from the field vibration tests and estimated using the calibrated finite element models considering the separation joint are found to be in good agreement.