As part of its work on massive wood construction, FPInnovations recently published the Design Guide for Timber-Concrete Composite Floors in Canada. This complete document, which is a complementary tool to the Canadian CLT Handbook, addresses different aspects related the design of wood floors covered with a composite concrete slab, a massive wood building approach that is little known in Canada but which could be better exploited.
A winning combination
Timber-concrete systems consist of two distinct layers, a timber layer and a concrete layer (on top), joined together by shear connectors. The properties of both materials are then better exploited since tension forces from bending are mainly resisted by the timber, while compression forces from bending are resisted by the concrete.
The addition of a composite concrete slab over the solid wood element allows, among other things, to improve the acoustics and vibration properties of the floor, a significant advantage in multi-family residential buildings. Its increased stiffness also allows for the use of larger floor spans where such spans would generally be more difficult to achieve with floors made entirely of solid wood. In addition, the concrete slab considerably stiffens the diaphragm effect, another advantage for multi-storey buildings.
For the moment, these floors are generally manufactured by transporting the wooden elements, on which connectors can be pre-installed in the plant, then a concrete slab is poured on site. However, a prefabrication approach is being studied, where the wood-concrete composite element would be delivered to the construction site, which would optimize the—already fast—construction time of mass timber buildings.
How to learn more?
You are interested in learning more on this subject? Don’t miss the free webinar hosted by WoodWorks/Canadian Wood Council and FPInnovations on July 8 at 2:00 pm (EDT) (register here).
It is also possible to get your copy of the Design Guide for Timber-Concrete Composite Floors in Canada and the Canadian CLT Handbook. Download the free pdf version or order a paper copy. Visit the clt.fpinnovations.ca webpage for more details.
For more information on timber-concrete composite floor systems, please contact Samuel Cuerrier-Auclair, engineer and researcher in FPInnovations’ Building System group.