Asce 20-96 Standard Guidelines For The Design And Installation Of Here

Calculate the pipe stiffness factor (PS) or D-Load for rigid pipes. Compare this to the required strength based on depth of cover.

| Type | Description | Bedding Material | Compaction | | :--- | :--- | :--- | :--- | | | Flat bottom, no haunch support | Native soil (poor) | Minimal | | Type 2 | Shaped bottom, limited haunch | Sand or crushed stone | Moderate (90% Std Proctor) | | Type 3 | Full haunch support | Well-graded granular material | High (95% Std Proctor) | | Type 4 | Concrete cradle | Controlled low-strength material (CLSM) or concrete | Not applicable | Calculate the pipe stiffness factor (PS) or D-Load

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. Contractors often believed that "more compaction is always