Identification of vibration direction of existing buildings using ambient vibration noise tests

This paper investigates the deviation angle between the principal axis of a building and its vibration direction based on in-site full-scale testing carried out on existing old buildings in Algiers (Algeria). It presents results of a study on 67 reinforced concrete existing buildings. Analysis of empirical correlations introducing geometrical characteristics and analytical frequencies of the selected buildings is performed firstly. Secondly, fundamental frequency measures of some 36 buildings were carried out using the ambient vibration technique. The study shows that each of the tested buildings exhibit a direction of vibration that does not coincide with its orthogonal axes.