Evaluation of Building Columns Subjected to Near-Contact Explosives

As evidenced by available test data, steel columns are susceptible to failure due to large, localized deformations and fracturing of the k-area when subjected to near-contact explosive loading. This paper describes a case study performed on two different steel columns subjected to near-contact loading from a person-borne improvised explosive device (PBIED) along with a retrofit developed to reduce the expected damage to the columns. The analysis was performed using a loosely coupled computational fluid dynamics (CFD) and computational structural dynamics (CSD) code. The CFD code models the detonation of the high explosive, propagation of the shock wave in ambient air, shock reflection from the floor and column, and overpressure loading on the column flange and web surfaces. The CSD finite element (FE) code captures the local displacement and deformation of the column. In this coupled approach, the movement of the column influences the airblast which in turn affects the loading on the structure.