Response of a Low Rise Steel Building to Air Blast

It has been suggested that building designed for strong ground motions will also have improved resistance to blast loads. As an initial attempt to qualify this improvement, the response of a three story steel building, designed for the 1994 building code, with lateral resistance provided by perimeter moment frames, is considered. An analytical model of the building is developed and the magnitude and distribution of blast loads on the structure are estimated using available computer software based on empirical methods. To obtain the relationship between pressure, time duration, and standoff distance, these programs are used to obtain an accurate model of the air blast loading. A hemispherical surface burst for various explosive weights and standoff distances are considered for generating the air blast loading. Linear and nonlinear analyses are conducted for these loadings. Air blast demands on the structure are compared to current seismic guidelines. These studies present the displacement responses, story drifts, stress distributions and inelastic demands.