Class 6F1 material is a selected granular material with a fine grading that is used for capping.
The grading requirements for this material are defined in Series 600 Earthwork of the Specification for Highway Works.
It can be produced using both quarried and recycled materials.
It is described in the the specifications as ‘any material, or combination of materials – including recycled aggregates with not more than 50% by mass of recycled bituminous planings and granulated asphalt, but excluding materials contaminated with tar and tar-bitumen binders, unburnt colliery spoil, argillaceous rock and chalk’.
If the material is to be used within the construction of highways then it must meet the specification set out in Series 600 Earthwork of the Specification for Highway Work.
Table 6/2: Grading Requirements for Acceptable Earthworks Materials Other than 6F4, 6F5 and 6S.
Sources:
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