Abstract
Laboratory and analytical investigations were conducted to study the effect of steel fibres and concrete matrix strength on the behaviour of ground slabs. Three full-scale (3 m x 3 m x 0.1 m) slabs were precast, placed on a rubber mat, resting on a concrete floor, and centrally loaded either to failure or to the maximum loading-jack capacity. The tested load-carrying capacity of each slab was compared to theoretically estimated values using the Meyerhof model. Test results indicated that the addition of 60 kg/m(3) (0.76% by volume) of hooked-end steel fibres to concrete significantly increases the load-carrying and displacement capacities, changes the mode of failure from brittle to ductile, reduces cracking on bottom and top surfaces of the slab and allows a significant reduction in slab thickness. Increasing the concrete matrix strength of steel-fibre-reinforced concrete slab from 45 to 85 MPa had a marginal effect on the load-carrying capacity of the slab at points on the displacement response beyond the first crack point. Furthermore, the Meyerhof model was found to underestimate the load-carrying capacity of the tested ground slabs.