Danish Technological Institute


Combined loading is defined as walls subjected to vertical and horizontal out-of-plane loading. These walls are typically three- or four-sided supported and with openings (see figure 1). Throughout Europe the design of walls subjected to combined loading has been rather different and the issue has been discussed in TC250/SC6 for many years.
In the Eurocode EN 1996-1-1 formulas are given for reduction of the effective height for walls without openings, but no guidelines are given for walls with openings. Using successive reduction factors gives an easy and consistent method for determining the effective height for walls with openings.
Determination of the eccentricity using frame programs does normally presume a certain connection in the joints between slabs and walls not always present. The rotation stiffness of the slab and the wall are parameters crucial to the eccentricity. These parameters can be implemented using an interval of eccentricities.
Eurocode EN 1996-1-1 is not quite clear in giving a unique and operational model for designing walls subjected to combined loading taking the flexural strength into consideration, though allowance for the principle is given through the ?fl concept. In this paper an operational method using the extended Navier Method is given.
References of formulas and tables in this paper are to EN 1996-1-1.

Key words
EN 1996-1-1, Combined loading, Flexural strength, Eccentricity, Effective height