Experimental study on the load-bearing capacity of detachable prefabricated concrete slabs with dislocated cover slab units for steel structures

A detachable prefabricated slab with dislocated cover slab units for steel structures, which consists of lower base slab units, upper cover slab units (dislocated covering the base slab units), and connection systems (including concrete shear keys with pre-buried bolts, steel sleeves, nuts, and washers), was proposed in this paper. The cover slab units, the base slab units, and the connection systems form a whole slab that has good continuity and integrity through a dislocated arrangement method. Meanwhile, the whole slab and steel beams are connected with demountable shear connectors. Therefore, this prefabricated slab can completely avoid onsite casting. In this paper, a comparative flexural test of the detachable prefabricated slab with dislocated cover slab units and a cast-in-place slab with the same overall dimensions was conducted. The load-bearing capacity, damage mechanism, stress distribution, and combined effect of the cover and base slab units of this new slab were revealed. A detailed solid-element model was established to investigate the effect of the loading methods on the load-bearing capacity and the failure mode of the slab. Meanwhile, the calculation method of the ultimate bearing capacity of the slab was proposed. This detachable slab without onsite casting can greatly improve the speed of on-site construction and realize the whole system assembly of steel structures.