Dynamic behaviour of flexible facade systems in tall buildings subjected to wind loads

In recent years many new devices, as energy absorber systems, have been introduced in tall building. But most of them have some disadvantages such as complexity of design and large spaces needed for their installation. Façade systems, as an integral part of high-rise buildings, and as non-structural systems are susceptible to potential failure when subjected to wind, if not designed properly. In this paper an alternative method using multi-skin façade systems as an energy absorbing device is proposed in order to decrease the amount of energy imparted to the main structure during high speed winds and cyclones. A series of elastic and inelastic time history analyses using SAP2000 have been carried out to assess the structural dynamic response of a proposed 45 storey building with reinforced concrete frame structure under a simulated harmonic wind load, which derived from three second gusts according to provisions of Australian wind code (AS/NZ 1170.2). The preliminary results indicate that it is possible to make use of the double skin façade system in tall buildings to work as a damper device, if the connections are properly designed, to minimise the wind induced vibrations of the primary structure as well as reducing inter storey drift.