Evaluation of Serviceability Assessment of Stadium Grandstands during Live Concerts and Football Matches

Since stadia host sporting events and rock/pop concerts, they were not originally designed for, some concerns arise on the loading that these civil structures have to support. Dynamic loads generated by people attending these events can be short random excitations like happens for goals during football matches and/or repeated periodic loading caused by motion synchronized with song rhythm. The achieved vibration level has to be analyzed against the serviceability levels given in existing guidance from two different points of view. The first regards the structure damages while the second concerns the evaluation of people perception from a disturbing to a panic sensation. The present work presents an analysis of the measured vibration levels of the Milano stadium (Giuseppe Meazza) during different events (13 concerts and 7 football matches) held between summer 2013 and summer 2014. These data are analyzed according to international standards (ISO 2631, ISO 6841, ISO 10137) and recognized national guidance in order to assess the stadium serviceability against people induced vibrations during different events and to critically face the limits imposed by the standards. To highlight how the different dynamic properties of the selected stands affect the measured vibration levels two stands (2nd and 3rd) having different dynamic response have been considered in the paper. The analysis shows that while the comfort limits are sometimes exceeded, the panic related limits are never reached, even if during rock concerts a strong horizontal motion of the rings stand is clearly perceptible. The obtained results can be considered as a reference to evaluate the performance of the standards and of structures serviceability.