Class 6I is a selected, well graded granular material used as a fill to reinforced soils and anchored earth structures.
The grading requirements are set out in Series 600 Earthwork of the Specification for Highway Works.
It can be produced using both quarried or recycled materials.
This includes, Natural gravel, natural sand, crushed gravel, crushed rock, crushed concrete, slag, chalk, well burnt colliery spoil.
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
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