Experiments investigating Concrete Floor Behaviour using Specific Reinforcement A.A. van den Bos 1 , H. Hofmeyer 1,2 1 ABT consulting engineers, Civil Engineering Group, Arnhem, The Netherlands, 2 Technische Universiteit Eindhoven, Structural Design Group, The Netherlands To reduce the surface crack width and to optimize the ultimate punching load of warehouse concrete floors, fibre reinforcement and special reinforcement mats above piles are used. Due to the special reinforcement mats, current design rules cannot be used to correctly predict the surface crack width and the ultimate punching load. Therefore, full-scale experiments have been carried out for six different reinforcement types. A fibre-reinforced floor with circular pile mat is the best solution, both for reducing the surface crack width and for optimizing the ultimate punching load. Keywords: Warehouse concrete floors, surface crack width, specific reinforcement, fibre reinforcement, ultimate punching load, experiments. 1 Introduction The utilization of warehouse floors involves the use of large amounts of material and labour and thus a lot of effort is spent on optimizing the floor design. Because the floor surface is visible and many warehouse floors have to be liquid retaining, owners complain about small cracks, even if they are completely acceptable to the structural engineer. Thus the surface crack width needs to be minimized. Secondly, to design a floor economically, one of the necessarily aspects is a precise prediction of the ultimate punching load. Current design codes are not suitable for finding the surface crack width and ultimate punching load for specific reinforcement types (for instance steel fibre reinforcement). A description and evaluation of the current European and American design codes is given by Albrecht (2002). On the subject of concrete floor punching, experiments were carried out using normal strength concrete (Richart 1948, Moe 1961, Kinnunen 1960, Andersson 1963, Regan 1984). More recently, punching was studied experimentally using high strength concrete with tests without shear reinforcement (Hallgren 1993, Tomaszewicz 1993, Ramdane 1996). Tests including shear reinforcement were also performed (Oliveira 1999, Lee 1999, Beutel 1998). Furthermore, on high strength lightweight concrete, Osman, Marzouk and Helmy (2000) investigated punching behaviour. All experiments mentioned were merely focused on the ultimate punching load rather