Furthermore, installation standards were dangerously vague. Contractors often believed that "more compaction is always better," leading to over-compaction that crushed flexible pipes. Conversely, poor bedding led to settlement and pipe rupture.
If you are an owner of an aging pipeline system, a review of your original construction documents will likely reveal the phrase “Designed in accordance with ASCE 20-96 Standard Guidelines for the Design and Installation of…” Understanding that document is key to rehabilitating those assets today. Furthermore, installation standards were dangerously vague
Use the Iowa Deflection Formula (modified by ASCE 20-96): Δy (%) = (DL * K * Wc * 100) / (144 * PS + 0.061 * E') Where E' is the soil modulus of reaction (depends on bedding type). The standard provides lookup tables for E' values. If you are an owner of an aging