This paper presents a summary of our current efforts in the assessment of the effectiveness of dampening of blast loads on building structures by designing cladding to act as a damper. The cladding system considered consists of concrete sandwich wall panels and laminated bearings as cladding supports. Layered structural elements are chosen for their inherited reflective boundaries at the interfaces between two layers of materials of different acoustic impedance. At transient state, applied blast load on the exposed face of a cladding panel sets the cladding panel vibrating and is transmitted to the cladding supports. The reflective boundaries within the cladding panel will reflect some of the stress wave at the interface between two layers. The thickness of the layers and the acoustic impedance of the different layers of the cladding can be adjusted so that the reflected stress wave acts against the follow-on incoming stress wave and thus reduces the instantaneous force at the supports.

This study has considered a case where the cladding to a building is subjected to an external source of explosion caused by a one tonne bomb blast at a distance of twenty metres. Sandwich panels are chosen for. this study to represent precast concrete cladding panels for buildings which have two skins of reinforced concrete wall with a cavity or a layer of insulation material between the skins. Various types of infill materials have been investigated for their effectiveness of dampening the applied blast load. The use of active dampers for cladding have also been investigated. The effects of debonding the different layers of the sandwich panels so as to prevent the transmission of certain types of stress wave have also been studied.

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