Seismic safety begins as early as in the construction phase

Connectors are classified into what are known as low-cycle ductility classes for application in earthquake-prone areas (e.g., Italy). By comparing repetitive and fully reversed cyclical bend test parameters, standard EN 14592 defines three ductility classes with increasing structural requirements. These classes are designated as S1, S2 or S3 in ascending order of “seismic performance”. Ductility denotes a material’s property of abruptly deforming and ultimately failing when placed under load. To determine the ductility class of the screws, the screws are bent at a specific angle alternately in up to three cycles. With each cycle, checks are performed to determine whether at least 80% of the yield moment of an unbent screw of the same type is still being achieved. If this is the case, then the screws are allowed to be classified according to their respective ductility class.

Wood construction screws from Eurotec with the highest ductility class

Eurotec delivers wood construction screws made of carbon steel with nominal diameters of 6.0 to 10.0 mm and screws made of A2/A4 stainless steel and nominal diameters of 5.0 and 6.0 mm, which have the highest S3 class. Among others, the wood construction screws with the highest ductility class include Paneltwistec and Topduo with an 8.0 mm diameter. The screws are characterised by their high strength but are still ductile and flexible enough without making the material become brittle and fail. As a result, it decreases the likelihood of such incidents where a wood-to-wood connection would suddenly fail should an earthquake hit.

Contact our experts at Eurotec for the optimal fastening methods. We are happy to assist and advise you on your construction project, taking into account the appropriate conditions.