Special Slab Systems

Abstract

A wide-slab floor consists of a prefabricated and a cast-in-situ component. The prefabricated component is a thin floor unit of 2.4 m width. This is the dark shaded part in Figure 17.1. The thickness is between 50 and 70 mm. These wide elements are placed side by side without connection and are supported by scaffolding. They are the formwork for the second component, concrete which will be cast in situ on top of these floor units. This is the light shaded part in Figure 17.1. The total slab thickness is between 150 and 250 mm. On top of the prefabricated floor units there is a truss-shaped reinforcement (hat-shaped cross-section). Jointly the floor unit and reinforcement truss act as an integrated girder to provide sufficient stiffness during transport. Furthermore, the truss reinforcement assures sufficient interlock with the concrete above the floor units. The units are either reinforced by mild steel (passive reinforcement) or pre-tensioned.