Simplified Damage Assessment Method for Buried Structures against External Blast Load

Abstract

Decoupling of soil-structure interaction is applied to analyze buried structure damage due to external blast load. The structural element under analysis is assumed to deform as a simply supported rigid-plastic beam. Shear failure, bending failure, and combined failure modes are considered based on five transverse velocity profiles. With proper failure criteria, the critical equations for structural shear and bending failures are derived respectively. Pressure-impulse diagrams are then developed to assess damage of the buried structures. Comparison has been made to show the influences of the soil-structure interaction and the shear-to-bending strength ratio of the buried structure. A case study has been conducted to a buried reinforced concrete box-type structure which shows that the proposed analysis method can be effectively applied.