Strength and behaviour of steel fibre reinforced concrete slabs subjected to impact loading

Abstract

Twenty two simply supported concrete slabs reinforced with nominal steel bars and steel fibres were subjected to either static loading or repeated impacts by a hemispherical nose falling mass. The dimensions of the slabs were (1000x1000x50 mm). The test variables were the steel fibre content, falling mass and height of drop. A special test rig was designed and fabricated to carry out static and impact tests. In each static test the load-deflection curve was determined in addition to the mode of slab failure. Load causing first crack and failure load were also recorded. For impact tests, maximum transient and residual deflections and the crater depth were measured with each impact blow. Number of impacts to cause first crack, initial and complete scabbing and slab failure were also recorded. Test results have shown that slabs reinforced with steel fibres exhibited considerable resistance to impact loading by producing smaller deformations and sustaining more impacts to failure than slab without fibres (plain concrete slab). The results also indicated that scabbing is remarkably reduced in the slabs reinforced with steel fibres compared to plain ones. (A) For the covering abstract of the conference see IRRD 862056.