When assessing surface regularity in FM areas it is not possible to survey an infinite number of points, therefore a representative sample of the floor is surveyed on a 3 metre grid.
Table 3.1: Permissible 95 percentile values on Properties E and F.
|Floor Class||Typical floor use||Property|
|FM1||Where very high standards of flatness and levelness are required.
Reach trucks operating at above 13m without side-shift.
|FM2||Reach trucks operating at above 8 – 13m without side-shift.||6.5||2.0|
|FM3||Retail floors to take directly applied flooring. Reach trucks operating at up to 8m without side-shift.
Reach trucks operating at up to 13m with side-shift.
|FM4||Retail floors to take applied screeds.
Workshops and manufacturing facilities where MHE lift heights are restricted to 4m.
|Note: Side-shift is the ability of a truck to adjust the pallet transversely to the fork direction.|
Properties E and F are checked as well as a check to datum
Property E to control levelness is the elevational difference in millimetres checked directly between fixed points 3m apart on a grid over the entire floor area. (not across diagonals)
Property F to control flatness, this is the change in elevational difference between two consecutive measurements of elevational difference each measured over 300mm.
No point on the Property E survey grid is to exceed +/- 15mm of a fixed datum plane
Table 3.1 shows an extract from the UK Concrete Society’s Technical Report 34.
Measuring Property E (and Datum check) using an Optical Level and Parallel Plate Micrometer, taking readings from an Invar Staff to 0.1mm.
Measuring Property F on site with our Property II Meter.
The Concrete Society’s TR34 Free Movement (4th Edition) Classifications
can be checked to ‘BS 8204-2:2003+A2:2011’ straight edge specifications SR1, SR2 and SR3
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