Headed studs in profiled steel sheeting transverse to the beam. Investigations on design resistance of headed stud shear connectors on the basis of the Final Draft of SC4.PT3 (April 2018)

The unsafety of current design rules for novel types of open-trough deck geometries for the resistance of headed studs in profiled steel sheeting is well known [1] and it was the main reason behind the nomination of CEN/TC250/SC4- Task SC4.T3: “Revised rules for shear connection in the presence of modern forms of profiled sheeting”.
During the RFCS research project “DISCCO” (RFCS-CT-2012-00030) [1], a mechanical model was
developed on the basis of a large literature study and previous studies [2, 3, 4, 5, 6] while the
corresponding design equations were presented by CEN/TC250/SC4.PT3 and further enhanced during the Research Project “ShearCON” of University of Luxembourg.
In order to let the current rules of EN 1994-1-1 6.6 (Eq.(2) and (3)) as unchanged as possible,
the limits of its suitable field of applicability (Database B1) was investigated thoroughly by means
of the statistical procedure of EN 1990 D.8 [7]. The newly proposed equations (Eq. (7) and (8)) apply only to the cases outside these limits (Database B2).
In this way, the proposed solution is able to restore the level of safety to its initial
value, so that the partial safety factor for the shear connection ϒV=1.25 is adequate.
Conversely, the current situation (without including the new design equations) would need a much
higher partial safety factor as shown below.