Rationale

Proposed updates include: • Replace Fig 2 for ovality with an equation for ovality factor (see attached buckling paper). Determine fo from using %deflection calculated from Eq. X2.7 and fo = (1-%deflection)^9. • Suggest fo be defined as "ovality compensation factor to account for stress caused by longitudinal bending. • Eq. 5 - suggest only list the Poisson Ratio that should be used in Eq. 5. • Table X1.1 - Add note stating that Elastic Modulus values are based on a test tensile load of 400psi. Elastic modulus values increase for lower tensile loads and decrease for higher tensile loads. • Eliminate Table X2.1. Deflection limits for both pressurized and non-pressurized pipe of all DR’s should be 8% (see attached bending and deflection paper) • Revise Table X3.1 per attached buckling paper. Note that Eq. 5 was used along with the Poisson value used. Note E-values from Table X1.1. • X2.2.1 - Explain why the Terzaghi friction angle is reduced by 50% or eliminate reduction • X2.6 - Rewrite • Update reference list with some more recent papers