Influence of the principal geometrical parameters of straight city streets on positive and negative phase blast wave impulses

This study is concerned with the effect of confinement, provided by tall buildings which border straight city streets, on the positive and negative phase impulses of blast waves originating from explosive detonations. An approach to the problem is described which is based on a parametric study comprising numerical simulations validated by comparison with small-scale experiments. Results of the simulations are presented in graphs of peak scaled positive and negative phase impulse, measured at locations near to ground level on the building facades, plotted against scaled distance along the centreline of the city street. A range of scaled street widths and building heights are considered which covers most cases of practical interest. The nature of the variation of both positive and negative phase impulses is described, and the implications for the design and hazard assessment of urban landscapes are considered.