A load supporting structure such as a bridge deck is mounted on two spaced beams and includes a pre-cast concrete panel with a plurality of transverse tension straps attached to the edges of the panel by anchoring studs attached to the tension member and embedded within the panel such the tension straps—prevent spreading of the panel so that loads are transferred from an upper surface of the panel to the beams by forming a compressive arch within the panel. A concrete deck slab is cast over the pre-cast panel and is attached to the tension straps by embedded anchor studs located on the straps outside the panel so as to form a compressive arch within the slab. The compressive arch loading avoids the use of tension reinforcing steel in the concrete which can corrode. The use of a pre-cast panel and cast slab simplifies assembly as no welding to the beams on site is required.