Husqvarna me-751413 Superfloor Construction Products Box 2098 Instructions
- June 13, 2024
- Husqvarna
Table of Contents
Husqvarna me-751413 Superfloor Construction Products Box 2098
information
General information on the choice of concrete and casting technique when producing a floor according to the Husqvarna SUPERFLOOR™ process.
NOTE!
Concrete floors are designed according to requirements depending on activity
and load.
The designer is always responsible for ensuring the requirements are met
regarding reinforcement and concrete quality as well as dimensioning.
For all exposed concrete floors, measures should be taken to minimize cracks and pores.
Cracks:
In general, larger aggregate (stone size) and high stone content reduce the
shrinkage and thus, the risk for cracking. If high quality aggregate is used
(in Sweden = granite), greater strength is also obtained. Therefore, aggregate
as large as possible (d-max) should be chosen, but not bigger than 1/3 of the
floor thickness. Agents to reduce shrinkage can be used with advantage.
It may be appropriate to saw crack initiators/joints at approx. 6m c/c. This
should be done relatively early, not more than 2 hours after the max.
temperature is attained in the concrete, which usually means sawing must be
done within 24 hours of casting.
Limit heat generation, especially in warm climates. Do not use higher cement
content than necessary.
Post curing is very important. Suitable methods include:
a ) Covering the surface with a vapor-proof layer, which is secured at
the edges and joints to prevent draughts.
b ) Laying damp covering materials on the concrete surface as well as
protecting the cover against drying out.
c ) Keeping the concrete visibly wet with suitable quantities of water.
Pores :
Vibration: Poor vibration results in unnecessarily many air pores. Excessive
vibration may result in the aggregate sinking and some areas of the finished
floor completely without visible stones.
Finishing: Thorough power floating and light power troweling are recommended.
Excessive troweling makes the surface difficult to grind. No troweling results
in more pores in the concrete surface.
Reinforcement and concrete:
Concrete reinforced with steel fibers is not suitable for Husqvarna
SUPERFLOOR™. We recommend traditional reinforcement.
Traditional concrete is preferable to self-compacting (SCC), because SCC
usually has a rough surface, more air pores and more uneven distribution of
the aggregate. SCC means a lower stone content and, possibly, also a risk that
the stones that do exist sink slightly during laying out and finishing Foreign
objects (slate, wood chips, pine cones, roots and suchlike) must be minimized,
as far as possible, in the concrete. Choose aggregate that does not contain
contaminants and make sure the form is clean prior to casting.
Coloring concrete is possible. Pigment is added to the fresh concrete at the
factory or in the concrete mixer truck on the way to the worksite. The
producer of the concrete will have more information about colored concrete.
Requirements on the appearance influence the choice of concrete grade
Because the appearance of Husqvarna SUPERFLOOR™ is dependent on the choice of
aggregate and the exposure of this, aesthetic requirements can also influence
the choice of the concrete quality. However, not to such an extent that the
concrete quality will not fulfil the designer’s requirements. Concrete quality
C28/35 is in general a suitable grade for Husqvarna SUPERFLOOR™, but also
other qualities are able to use. However, if a higher concrete quality is
used, it is usually a bit more difficult and time-consuming to expose the
aggregate. If a lower grade is used, it is easier to grind, but this usually
results in more air pores.
Other points to consider:
Before placement:
- Inform the concrete supplier that the concrete will be a polished floor, so that they can, hopefully, offer an optimal/adapted recipe for this purpose.
- Clean the mold/formwork before pouring the slab. Make sure that any loose styrofoam is removed that will else position itself in the top layer of the concrete creating unwanted marks during grinding/polishing.
During placement
-
Point out that the concrete should be rotated/mixed during transport, and for at least 5 minutes at maximum speed at the site before discharging commences. (This is to ensure that the stone fraction is distributed as evenly as possible in the concrete.)
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Vibration: Poor vibration results in unnecessarily many air pores. Excess vibration may result in the aggregate sinking and some areas of the finished floor completely lacking visible stones. NOTE! When vibrating, the poker shall never be used flat in the concrete, but either Vertical (90°) or max. 45° tilting.
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For laser casting: Never transport concrete with the internal vibrator. This entails a risk of over-vibration and separation.
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Do not walk on the concrete any more than necessary. This is to prevent the stones from being pushed down. Use special shoe protection while troweling to avoid permanent footprints afterwards
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Polypropylene fibers, for example SIKA Crackstop, can be used to reduce the plastic shrinkage. They also help to maintain a more even aggregate structure in the concrete.
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Finishing: Thorough power floating and light troweling are recommended. Excessive troweling makes the surface difficult to grind. No troweling results in more pores in the concrete surface.
NOTE! When power floating: The use of floating discs increases the overall flatness of the concrete slab and helps reducing the number of passes with the sequential finishing or combo blades. Also, make sure the first pass is run at 90°angle to the pass done with the beams/screed and with discs at low rotor speed. This helps to clean the surface, otherwise the machine has a tendency to follow the waves that the screed may have created/left. -
Otherwise, refer to the European standard for Concrete, SS EN 206 – 1.
After placement (before grinding)
-
Hardening: If possible, avoid any covering during the first week after placement. Instead, water frequently and keep the surface moist. Covering the surface using plastic sheets is efficient but also risks uneven drying. And uneven drying this will risk create visible patterns and darker spots in the hardened concrete.
Note! At air temperatures of +5 degrees and lower, adding water in connection with hardening is not permitted. Here a plastic sheeting ca be a necessary alternative. If so, the sheeting should have an overlap of at least 150mm at joints. It is important that the sheeting is sealed against walls or outer edges, otherwise differences in color will arise. The circumstances (wind, temperature) may mean that measures such as, for example, misting unit, are needed immediately after casting. At the minimum, hardening should be done to Hardening Class 3 in accordance with Execution Standard EN 13670. -
Avoid placing building material on the newly placed slab before it has had time to dry properly since this risks create permanent marks and discolorations that will appear when grinding.
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If any material needs to be placed, use trestle work to place the material on.
No constraints?
If no consideration is taken to the requirements of dimensioning for activity
or load, consider the below specifications as a guideline for placing a
concrete slab optimal for grinding and polishing.
- Concrete quality C28/35 (equal to a 4000 psi concrete mix). Concrete quality should not be less than C25/C30 (3500 psi)
- No admixtures (if at all possible)
- W/C ratio: <0,55
- Slump: < S4 (<210mm or 8,3”)
- Finish to Floor Flatness (FF) > 50
- Floor Levelness (FL): n/a
- Place, strike off, pan/consolidate, finish with troweling using steel or plastic finishing blades or combo blades to meet above spec.
References
Read User Manual Online (PDF format)
Read User Manual Online (PDF format) >>