Some Topics About Wind Engineering that Curtain Walling Design Might Be Longing for in Standards

Abstract

Curtain walling is assuming more and more a leading role in tall building architectural design.

From a structural standpoint, there is no doubt that the wind action is the main loading condition, governing all the dimensioning of any curtain wall single component. On the other hand, the wind action is sensitive to any curtain wall local shape discontinuity, or composition peculiarity, which may modify the load intensity on a micro-scale, but still important for structural safety.

On such respect, the structural engineer may have to cope with some recurrent issues:

• to define wind loads during an initial tender phase, when no wind tunnel test has been developed yet;

• to define wind loads for the cladding of a building that will never have the aid of a wind tunnel test;

• to define wind loads on components that have not been simulated in the wind tunnel test, because their size was too small when scaled to the wind tunnel test model.

Published standards are the main support to this activity, but this paper will show some frequent cases that are still missing, or just partially treated, in the international standards, like:

• Façade projections, i.e. canopies, balconies, sun-shadings, etc.;

• Buildings with curved surfaces but non-circular shape;

• Cladding elements with more than one skin.

Examples from the everyday design work will be shown.