ILEK University of Stuttgart, Stuttgart
Textile reinforced concrete has developed in recent years into a construction technique that has its benefits and advantages in applications where conventional types of reinforcement have their limits. The current, minimum slab thickness for steel-reinforced concrete façade slabs is 7.0 cm; this is due to the minimum, required concrete cover to ensure adequate corrosion protection. Façade slab anchors for these slab thicknesses are building authority approved.
As corrosion protection is not an issue for textile reinforced concrete, the minimum thickness for the concrete cover can be significantly reduced. The requirement for component thickness is now determined by the load-bearing capacity and by production-related boundary conditions.
For practical building reasons, a panel thickness of 3.0 cm has proved to be the best choice.
Compared to steel-reinforced façade panels, this is a weight and thickness reduction of almost 60%.
Thin concrete elements are of great interest in cases when the thickness or the weight of the panels is largely limited e.g. because of adjoining concrete elements in renovation or upgrade projects, retrofitting or improvements. Compared to other building materials, concrete has characteristic advantages in building physics and fire protection properties, irrespective of the thickness.
Obviously, minimal thicknesses place extra demands on planning and construction. Especially effects on concrete, punching, splitting and concrete breakout must be examined in experiments. Those tests are best done on a large scale to examine the interaction of concrete, reinforcement and local load introduction by the fixing element.
This is an overview of calculation and test methods. Results are provided to show the bearing behaviour of fixings in thin, textile reinforced concrete slabs. The design rules are explained and the results are illustrated.