Review of the basics of state of the art of blast loading

When a high explosive charge detonates in the proximity of an above ground structure, blast waves impact the structure over time and cause different levels of damage and possible collapse of the structure depending on the type of explosive detonated and the size of the charge weight used. Such an event occurs when a building is subjected to an uncontrolled demolition resulting from the actions of an IED. For a structural engineer to design in advance for such an event that must be anticipated at the start of the design process both for the type of explosive and the charge weight that may be used is, to say the least, an extremely difficult proposition considering there are presently no Australian standards or codes to refer to. The blast will see three pressures impact the structure and these are incident pressure (Pso), reflected pressure (Pr) and dynamic pressure (qs) (Ngo et al., Electron J Struct Eng 7:76–91, 2007a). The latter is the smallest of the three whilst the remaining two produce the largest pressures. The question that therefore arises is as to which of the largest pressures to use in designing a structure against blast loadings. Examples exist worldwide as to the outcome of buildings not being designed to carry blast loadings (Yan et al., Eng Fail Anal 51:9–19, 2015) which has inevitably resulted in the total collapse of the structure resulting in death or injury to those unfortunate enough to be caught inside the building as it collapsed. Structural designers design for many loadings such as dead loads, live loads, wind loads, and earthquake loads but the application of blast loads is not the norm and so only carried out in exceptional cases.