Backfill materials (Appendix A1) Previous Next Class A – Graded granular materials (A1.1) Class B – Granular materials (A1.2) Class C – Cohesive/granular materials (A1.3) Class D – Cohesive materials (A1.4) Class E – Unacceptable materials (A1.5) Field identification tests (A1.6) Field identification test No 1 – Silt identification Field identification test No 2 – Clay condition Field identification test No 3 – Granular condition Field identification test No 4 – Granular grading Previous Next