Stabilization of thin‐walled profiles under uplift loads

Sandwich panels are able to support their sub-structure against failure due to loss of stability. Especially for thin-walled Z-profiles used in lightweight metal construction as purlins, customary span-lengths often only can be reached by taking into account stabilization effects, which can be described as a combination of diaphragm and torsional restraint. However, for the load combination of dead weight and wind suction, the diaphragm is usually located on the flange under tensile stress, which means that only marginally stabilization effects can be added to the system. In addition, acc. to the German NA to DIN EN 1993-1-3, no stabilization due to a torsional restraint may be used for the aforementioned load combination. Recent investigations showed on the one hand that the reduction of the torsional restraint under uplifting loads stated in the literature is true, but on the other hand the investigations also provides a quantification of this reduction others than the rough engineering assumptions of 100 % to 50 % reduction often used in the past. Thus, a qualified estimation of the applicable torsional restraint under uplifting loads is possible, based on component tests and FE-calculations and derived from a mechanical model. The paper describes the scientific background as well as the mechanical model. Krieglstein, T.; Lener, G.; Naujoks, B.; Kühn, B. (2022) Stabilisierung von ZKantprofilen unter abhebenden Lasten. Stahlbau 91, H. 3, S. 162–171. https://doi.org/10.1002/stab.202100100 Stabilization of thin-walled profiles under uplift loads E D I T O R ’ S R E C O M M E N D A T I O N S