Scale effect and combined loading of thin UHPFRC members

Abstract

Ultra-high performance fibre reinforced concrete (UHPFRC) with a maximum aggregate size smaller than 1 mm is a very suitable material for very thin members or structures, like e. g. shells. With a fibre content of about 2% per volume this material fulfils the minimum reinforcement requirements e. g. of the German concrete code DIN 1045-1 (2001–07). Apart from the high strength, the high density of UHPFRC is favourably used for special structures like containments. Therefore, a joint research project on hot-water tanks was carried out at the University of Stuttgart by the institutes ILEK (Institute for Lightweight Structures Conceptual and Structural Design) and IWB (Institute for Construction Materials). At the IWB Reinhardt and Joos performed different types of density tests (see e. g. Reinhardt and Joos (2004)), which proved that UHPFRC is over 40 times denser than normal strength concrete and about 6 to 7 times denser than high performance concrete. At the ILEK the two authors examined the main properties for tank design, like the compressive strength, the tensile and the flexural strength of UHPFRC with a fibre content of 2% per volume, see e. g. Reineck and Greiner (2004) and Greiner (2006).