Combustion of Hazard Division 1.3 M1 Gun Propellant in a Reinforced Concrete Structure

This document describes the results of four tests involving the combustion of M1 gun propellant, an HD1.3 material, burning in a reinforced concrete structure. Chapter I presents an overview of the four tests, major test results, discussion, summary, conclusions, and recommendations. Chapters II through V present a detailed discussion of each test by chapter. Chapter VI presents a summary of the modeling effort that supported the study. Some major findings include the following. (1) If the flow from the structure is unchoked (Tests 1 and 3), the pressure in the structure remains on the order of 1 to 2 psi, and the structure survives. The major hazard is the hot plume exiting the structure and radiation from the plume. (2) If the flow from the structure is choked (Tests 2 and 4), the pressure in the structure rises until the structure fails. The pressures at rupture were 47 and 34 psi for Tests 2 and 4, respectively, at 1.4 and 2.3 seconds. (3) Structural debris was formed at rupture and projected significant distance from the original structure. Some debris were large, exceeding 1,000 g (largest fragment was 11,555 g), and were projected over 400 feet. The projected distances of many fragments exceeded the inhabited building safe-separation distances. A huge fireball was formed and burned intensely for about 15 seconds. Direct impingement of the fireball and radiation are hazards that must also be considered in addition to the formation of structural debris. The original document contains color images.