Centres of rigidity in multi-storey asymmetric diaphragm systems for general lateral static loading

Abstract In this paper a general methodology for calculating the centres of rigidity in multi-storey asymmetric buildings is proposed, which is applicable to orthogonal as well as to non-orthogonal diaphragm systems with complex topology and possible coupling of diaphragms along with consideration of very general load conditions, including gravity and modal loads. The methodology is presented in two alternative forms: (a) In the standard form, matrix relations have been developed which can be directly included to any new or existing programming codes for analysis of building structures, (b) In the alternative form the methodology can use the results of any standard programs for static analysis of building structures, in addition with a small post-processing effort that can be achieved by only few hand calculations, thus becoming significantly simpler than the methodologies that currently exist. A numerical example presents the individual steps of a comparative application of the standard and alternative forms of the methodology, while two additional numerical examples demonstrate the simplicity and efficiency of its alternative form.