masonry

honeycomb core

progressive collapse

tubes

ship structures

blast loading

size effect

low velocity

concrete containment

Structures

Rising fanaticism and rapid industrialization across the globe make the structures more vulnerable to direct threats generated from accidental and explosion-induced air-blast loads. Unlike the response of the reinforced concrete structure under quasi-static loading, it may respond in a brittle manner with highly localized failure like scabbing, cratering, spalling, and crushing of the concrete as well as rupturing of the reinforcement under the near field or contact detonations. Large deflection and high stresses could cause irreparable damage or result in the failure of critical structural elements. Besides, high-speed secondary fragmentation resulting from spalling of concrete may cause injuries to the occupants and other damages in the detonation area. It is therefore important to have a better understanding of the structural response/damage under air-blast loadings. This paper provides a comprehensive review of major (over twenty) publications addressing the blast response of the reinforced concrete slabs. First, the phenomenon of spall damage in the slab and the parameters affecting it are discussed. Then, available experimental investigations on slabs have been reviewed and different damage/failure modes of the slabs exposed to contact or close-in detonations are presented. The damage in the slabs has been observed in the form of spalling of concrete, the formation of punching crater, concrete scabbing/crushing, flexure-shear failure, flexural failure, bending-punching failure, and development of longitudinal, transverse, and radial cracks. Next, numerical modeling of the slabs using various material damage models available in different finite element programs has been discussed by reviewing the numerical /analytical investigations under air-blast loading. It is noted that the vast majority of the papers focused on improving the blast resistance of the slabs using different strengthening techniques. Finally, the major findings and other aspects that need to be considered for subsequent research are discusse...

Experimental and numerical investigations on performance of reinforced concrete slabs under explosive-induced air-blast loading: A state-of-the-art review