Derivation of a General Reflection Coefficient of Blast-Loaded Buried Structures

AbstractA general reflection coefficient (GRC) is defined to determine the equivalent uniform stress on an underground arched structure subjected to a subsurface explosion. The single-degree-of-freedom model approach is adopted and the structure–medium interaction and curvature effect are considered. The derivation lies on a virtual work method, which provides the GRC of the buried arch-shaped underground structure. The GRC is also suitable for box-shaped underground structures when the curvature of the arch tends to be zero. Case studies are discussed to investigate the effect of dimensionless parameters. The developed method is applied to a practical example. It is shown that the present approach is effective and applicable for practical use designing buried underground structures subjected to subsurface explosions. It also complements the current design codes, which lack details for designing arch-shaped buried protective structures.