Openings and service holes are regularly required through composite slabs to allow services to pass from floor to floor. A summary of industry best practise and guidance for SMD floor deck products can be seen below.
Openings can be grouped by deck profile and size:
When forming voids, the following should be noted;
- Voids should be boxed out and the deck cut after the concrete has cured
- Non-percussive cutting methods should be used to minimise disturbance of the composite bond between deck and concrete
- Voids should be isolated and not closely grouped
- Minimum spacing should be the greater of 300mm or 1.5x diameter, from edge to edge
- No more than ¼ of total span length should be removed
- Responsibility of design for additional reinforcement, trimming steels and structural verification lies with the project engineer
- Concentrated loads should not be applied near void locations
For more information on this topic, see our TGN Section 5.6 specifically relating to Forming Service Holes.