Use of an Aerodynamic Obstruction to Shield a Blast Door--Results of an Experimental Model Test.

Triangular prismatic aerodynamic obstructions can be used to shield a blast door. The objectives of this project were to evaluate the protection afforded by an obstruction and to determine the relative width of obstruction required to protect a given width of entrance. A study was performed from which similitude relationships were developed. A series of tests was conducted in which a protected and an unprotected model structure were subjected to blast waves from explosive charges. A 45-degree triangular prismatic obstruction was used to shield the protected structure. Fifteen variations of width and position of obstruction were evaluated. Results show that at the 100-psi overpressure level an obstruction 1 door-height high and 2 door-widths wide placed from 1 to 2 door-heights away from a structure can reduce the peak reflected pressure by 50. Author