Double Tee flooring units consist of two prestressed ribs and a connecting
top slab. The ribs can vary in depth from 200 to 500mm.The connecting slab
is 2400mm wide x 50mm thick. Double Tees are ideally suited for larger spanning
floors with a wide variety of services suspended from the flooring system.
Double Tees can easily accommodate large floor voids/penetrations through
the slab region.
A major practical benefit of a concrete floor is its ability to reduce
noise transmission. Double Tee concrete floors are quiet and do not creak
with temperature and moisture changes. The table below shows sound transmission
ratings achieved by Double Tees.
Double Tee concrete strength = 42 MPa.
Topping concrete strength = 20MPa.
Topping thickness = 65 mm
FIRE RESISTANCE RATING
2400 wide unit = 90 minutes For Fire Ratings or loads in excess of the
allowable shown, please contact your local Stresscrete branch.
Where high shear loads are combined with support beams or walls of low
material strength, a bearing capacity check according to NZS3101 should
be made; e.g. masonry bearing walls.
Lift Double Tees only at the lifting points provided. Chains or
strops must be of correct length to carry equal load and must not be more
than 300 off vertical.
Double Tees if stored on site must be supported at their ends on firm
ground. Bearers between layers in a stockpile must be vertically above each
other and units of varying length should not be stacked upon each other.
Ensure the bottom bearers are not pushed into the ground, resulting in the
bottom unit being supported near midspan.
Flange supported Double Tees must be bedded on a sand cement mortar (the
consistency of blocklaying mortar). This must be evenly spread just prior
to the unit being placed. Double Tee legs should be placed on cement mortar
or on plastic bearing pads. Stresscrete Double Tees are designed as prestressed
sections as per NZS3101: Part 1:1995. For minimum seating requirements refer
to NZS3101: Part 1:1995, section .3.6.4.
FURTHER TECHNICAL INFORMATION
Specifications for the manufacture, transport and erection of Double
Tee units, and standard details for typical situations, are available from
your nearest Stresscrete branch. Experienced and qualified staff will be
pleased to discuss design and fixing details. Refer general notes on page