Suspended Roof of Braga Sports Stadium, Portugal

Abstract

Temporary ambient vibration monitoring of the suspended roof of the new Braga Sports Stadium was developed with the purpose of identifying modal properties through operational modal analysis. This experimental work allowed the validation of a numerical modeling that takes into account the geometric nonlinear structural behavior and the progressive application of loads during the construction phase. Special attention was given for the identification of modal damping ratios, owing to the necessity of analyzing the susceptibility of the suspended roof to buffeting effects. Modal damping ratios were estimated from data provided by free, forced, and ambient vibration tests, using an improved implementation of the enhanced frequency domain method and the covariance-driven stochastic subspace identification (SSI-COV) method.