Anna Palisson

Consulting Engineer
Sokol Palisson Consultants
53 avenue Hoche
75008 PARIS




This module presents the design by calculation developed within the GRISPE project for steel decks with outwards stiffeners. Upper flanges of some steel deck contain outwards stiffeners in order to increase the shear connection between the steel and the concrete in a composite slab. Such steel decks are often used in steel-framed construction.  But the European Standard EN 1993-1-3 dealing with design rules for cold-formed members and sheeting does not cover profiled sheeting with outwards stiffeners during construction stage. Moreover there was a real lack of data and knowledge about resistance and stiffness of steel profiles with outwards stiffeners. Therefore a methodology to design by calculation of steel decks with outwards stiffeners was developed to fill in a lack in design rules. After this introduction of the topic and of the reason why this methodology was developed, this module first describes how this methodology was carried out. It presents the extensive test program of global behaviour of steel decks which was performed in order to provide required data. It gives the results of the analysis of the testing and of the calculation based on the methodology developed within GRISPE project Second it explains how to take into account the outwards stiffeners to determine the effective section and the resistance of a steel sheeting (Amendment proposed to CEN TC 250/SC3/WG3 EN 1993-1-3) Last it introduces the excel sheet which was implemented to calculate span moment resistance, for a profile with outwards stiffener in the upper flange, and with 2 stiffeners in the lower flange.


After the module, you will be able to …

  • remember why upper flange of some steel decks contain some outwards stiffeners
  • comprehend why the development of a design by calculation for steel decks with outwards stiffeners was necessary
  • apply, in the calculation, the correct yield stress for outwards stiffener in the sheeting flange
  • … to take into account intermediate outwards stiffener in the sheeting flange, in design by calculation
  • calculate the moment resistance of sheeting with outwards stiffeners
  • … evaluate the effective section of sheeting with outwards stiffeners