Class D – Cohesive materials (A1.4)

A1.4.1: Cohesive materials at the time of compaction must have a moisture content of between 0.8 and 1.2 times the plastic limit or be acceptable when subjected to field identification test No. 2.
A1.4.2: Clays that contain insufficient moisture when excavated, or have dried excessively during site storage, as defined by field identification test No. 2, may only be re-used provided that they are wetted to comply with A1.4.1 and compacted in accordance with A8. for Class D Cohesive Materials.
A1.4.3: It may be difficult to compact cohesive materials to uniformly achieve an adequate bearing capacity. Undertakers must select a lump size for clays within the limits specified in A2 and must ensure that all compaction equipment is operated within the requirements of A8. Failure to comply with A2 or A8. will result in unacceptable settlement and variable bearing capacity.
A1.4.4: High silt content materials, as defined by field identification test No. 1, must be compacted in accordance with A8. requirements for Class D Cohesive Materials.