Innovative Reinforcement for Fabric Formed Concrete Structures

Using fabric formwork, it is possible to cast architecturally interesting, optimised structures that use up to 40% less concrete than an equivalent strength prismatic section, thereby offering significant embodied energy savings. This paper reports on the latest techniques for the design, optimisation and shape prediction of fabric formed concrete beams before new test results of an innovative anchorage method for both steel and fibre reinforced polymer longitudinal reinforcing bars are presented. Two 2m span beams were tested and the ‘helically confined splayed bar’ was shown to provide full anchorage in both cases. The two beams both exceeded their design capacity and showed remarkably similar behaviour at the serviceability limit state, with the steel reinforced section going on to display considerable ductility. Potential areas of future development are then highlighted, with the use of woven advanced composite fabrics as participating formwork for both beam and shell elements being of particular interest.