RESPONSE OF FIBROUS-REINFORCED CONCRETE TO EXPLOSIVE LOADING

Abstract

Abstract : The results of 72 explosive loading tests on fibrous-reinforced concrete slabs are presented. The slabs, 32x32x4 inches, were tested in a vertical position with 4 inches of bearing on the two vertical sides. A 10- pound cylindrical charge of Composition B high explosive was used as the loading mechanism. Various synthetic and steel fibres were used as random reinforcing to develop a concrete that would resist explosive loadings. Evaluation was based upon the ability of the fibrous concrete to reduce the amount and velocity of fragments produced by the explosive loading. The values obtained from tests of plain, unreinforced concrete slabs were used as the basis of comparison. It is shown that when plain concrete slabs are reinforced conventionally to resist the shear and flexural stresses, there is no reduction in fragment velocities or fragmentation; and, that similarly reinforced slabs of fibrous concrete show 20% reduction in velocities, and over 80% reduction in fragmentation. A study made to evalute high-strength and medium-strength concrete, when used in conjunction with fibres, revealed no significant difference in response under the explosive loading. The mode of failure for a slab supported on two sides only is shown to be primarily flexural. Detailed descriptions of each individual test are presented, together with conclusions and recommendations for future work.