Assessment of Insulated Concrete Walls to Close-In Blast Demands

Abstract

Intentional and accidental impulsive loads from high-explosive detonations and munitions can result in significant damage to both civil and military facilities. One demand scenario of particular concern occurs during close-in detonation of high explosives. Even for resilient construction methods, such as reinforced concrete walls, these demands can produce undesirable effects including localized spall and breach. A popular form of exterior cladding in the United States consists of precast concrete insulated wall panels. These systems include an exterior concrete wythe, foam insulation layer, and an interior concrete wythe. While insulated wall panels are used to provide an energy-efficient building envelope, the insulation layer can provide a means of mitigating spall and breach of the panel. Thus, the performance of insulated wall panels subject to close-in blast demands is investigated. Both numerical simulations and experimental tests are carried out in order to assess the structural response of this wall system to close-in explosions. The results indicate that the use of insulated concrete wall panels provides enhanced resistance to spall and breach. This improvement is due to the sacrificial performance of the exterior wythe of the concrete panel and the increased standoff distance between the protected face and the threat provided by the insulation layer.