A correctly designed and constructed ground bearing concrete slab combines the advantages of hard wear, long life and the ability to carry heavy loads at low costs. The purpose of a ground bearing slab will vary according to application and each project requires its own individual characteristics, including strength, abrasion resistance, flatness and aesthetics. An important factor commonly taken into consideration is speed of construction and the savings that accrue from fast-track construction.
With the advent of tall narrow isle racking, to maximise storage capacity, flatness tolerances have become tighter. The benefits of large bay construction, both in terms of speed of floor installation and the reduction of long term maintenance a traditional joint requires have lead to some innovative solutions in the concrete performance, reinforcement and jointing areas of the market.
The Concrete Society’s TR34 4th Edition has been written by industry for industry and introduces a number of significant changes to the way that concrete industrial floors are designed and constructed in the UK with comprehensive guidance on new areas such as the design of steel fibre piled slabs and maintenance.
Constraining concrete shrinkage values due to drying, can help to prevent cracking and reduce the widths of movement joints. This can take the form of carefully selected concrete mix designs to include high range water reducing admixtures and constituants selected to reduce shirikage.
Innovative leave in place formwork and load transfer jointing systems help to maximise the fast track benefits of large bay construction whilst allowing the required movement in the slab during its life time, and in some cases, maximising the smooth operation of vehicle handling devices over the joint and minimising maintenance requirements caused by an uneven joint.
Whilst traditional steel mesh reinforcement can be used, steel fibre reinforcement can also be utilised, this may reduce the thickness of floor required and increase production rates.
The use of a fibre suppressant or dryshake topping material also increases abrasion resistance, asthetics and if required allows a coloured floor to be produced.