Those peculiar structures in cold-formed steel: racking & shelving

One of the applications of cold-formed steel in which a considerable tonnage is involved is corrugated steel sheets for wall and roof cladding. Another is racking and shelving (R&S), those peculiar spatial steel structures used for economic and logistics-effective storage of goods in warehouses. R&S has to be flexible in use and therefore adjustable. It has to be competitive by providing mass production in combination with standardized components. The use of cold-formed steel members and components was already matter of course at the very first stage of the development of R&S products around World War 2. Flexibility in shape and material leads to cost-effectiveness in combination with special connections to realize adjustability. Considering the non-traditional R&S detailing, the structural Eurocodes do not provide sufficient guidance to the rack designer for quite a number of design phenomena. Thus, the steel and racking industry, organized in the European Racking Federation ERF/FEM R&S, a member of the European Federation of Materials Handling (FEM), worked out a pan-European approach to the harmonization and standardization of R&S structural design and use. However, it took until 2008/2009 to have EN standards published, following the first FEM codes in 2000-2002. For the cold-formed members and components typically used in R&S structures, insufficient analytical approaches are available, or they have to be validated by tests. Design assisted by testing is a substantial part of R&S structural engineering. With the publication of EN 15512 in March 2009 for adjustable beam pallet racking, a number of European testing laboratories were commissioned by the racking industry to conduct the obligatory testing, resulting in intensive collaboration between the R&S industry and science, e.g. ECCS TWG 7.5. This paper gives an impression of R&S structures, the structural engineering challenge, the present state of the art and developments as well as the research still needed.