Class 6H is selected granular fill material that is used as a drainage layer to reinforced soil and anchored earth structures.
The grading requirements are defined in Series 600 Earthworks of the Specification for Highway Works.
Class 6H can be produced using quarried & recycled materials
This includes materials such as Natural gravel, natural sand, crushed gravel, crushed rock, crushed concrete, chalk and well burnt colliery spoil.
Table 6/2: Grading Requirements for Acceptable Earthworks Materials
Table 6/5: Imported Onto Site Grading Requirements for Class 6 Acceptable Earthworks Materials
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