12The HENSOTHERM® 420 KS fire-protection coating system manufactured by Rudolf Hensel GmbH was recently the first product in the world to receive general construction authority approval (abZ) for use on steel tendons with a solid circular cross-section or a hollow circular cross-section. With the aid of this reactive fire-protection system, a fire-resistance time of up to 60 minutes can be achieved for these sections.
Steel tendons with solid circular cross-section are used in the construction industry for bracings, trussed structures and for suspensions. Prefabricated tension rod systems are particularly common here. By applying reactive fire-protection coatings, such structural components can be protected against fire exposure. The usually delicate-looking steel structures can retain their architecturally eye-catching appearance by coating them with HENSOTHERM® 420 KS. This is a significant advantage over other protective measures, which also require more material and more time.
Several years of scientific investigations by the Bundesanstalt für Materialforschung und -prüfung (German federal institute for materials research and testing) form the basis for the approval procedure of the Deutsches Institute für Bautechnik (German institute for civil engineering), which can provide assistance in verifying the usability of reactive fire-protection systems on steel tendons.