“Modern Sewer Design” is the result of a - Jensen Bridge & Supply

Flow Regulators..............................................................................194Subsurface Disposal of Storm Water..............................................196Infiltration Basins ..........................................................................196Infiltration Trench ..........................................................................196Retention Wells ..............................................................................199Soil Investigation and Infiltration Tests..........................................200Field Tests ......................................................................................201Laboratory Methods ......................................................................201Indirect Methods ............................................................................203Subsurface Disposal Techniques ....................................................203Linear Recharge System ................................................................203Point Source and Recharge System................................................204Combination System ......................................................................204Design Example..............................................................................209Determination of Pre-Development Peak Runoff ..........................209Exfiltration Analysis ......................................................................209Exfiltration Calculations ................................................................209Construction of Recharge Trenches ..............................................212Trench in Permeable Rock and/or Stable Soil ..............................212Trench in Non-Cohesive Soil or Sand............................................212Perforated Pipe ..............................................................................213Synthetic Filter Fabrics ..................................................................215Pipe Backfill ..................................................................................215Chapter 7Chapter 8STRUCTURAL DESIGNIntroduction ....................................................................................217Loadings ........................................................................................217Live Loads ......................................................................................217Dead Loads ....................................................................................218Design Pressure ..............................................................................218Strength Considerations..................................................................219Handling Stiffness ..........................................................................220Deflection ......................................................................................223Seam Strength ................................................................................223Pipe-Arches ....................................................................................224ASTM Standard Practices ..............................................................224Design Example..............................................................................225Depth of Cover ..............................................................................226Installation and Backfill of Spiral Rib Pipe ..................................229Aerial Sewers..................................................................................242Design Fittings ..............................................................................242Structural Design for CSP Field Joints ..........................................244DURABILITYIntroduction ....................................................................................251Factors Affecting CSP Durability ..................................................251Durability in Soil............................................................................251Durability in Water ........................................................................253Resistance to Abrasion ..................................................................253Field Studies of Durability ............................................................254State Studies ..................................................................................254AISI Study......................................................................................255NCSPA/AISI Study ........................................................................255Canadian Studies ............................................................................255Coatings for Corrugated Steel Pipe................................................256Metallic Coatings............................................................................256Non-Metallic Coating and Pavings ................................................256Project Design Life ........................................................................259Durability Guidelines ....................................................................259Environmental Ranges....................................................................259Abrasion ........................................................................................259Abrasion Levels..............................................................................259Service Life of Metallic Coatings ..................................................259