PE Pipe - Post Installation Loads and Deflections

Post Installation Loads and Deflections

Earth Pressure Coefficient:

Θ – Internal Friction Angle of Soil (degree)

Arching Factor:

H – Depth of the Borehole below Ground Surface (ft)
B – Internal Bore Diameter (inch)
δ = Θ

External Earth Pressure:

γ – Unit Weight of Soil (lb/ft3)

Net External Pressure:

External Pressure Deflection:

E – Apparent Modulus of Elasticity (psi)
DR – Standard Dimensions Ratio

Buoyant Deflection:

γ_w – Unit Weight of Fluid in Borehole (lb/ft3)
D – Pipe Outside Diameter (inch)
I – Moment of Inertia of the Pipe Cross-Section (inch4/inch

t – Pipe Wall Thickness (inch)

Deflection due to Reissner Effect:

μ – Poisson’s Ratio
R- Radius of Curvature (ft)

Ovality Compensation Factor:

f₀ – Ovality compensation factor based on % of Deflection (𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑂𝑣𝑎𝑙𝑖𝑡𝑦)

Critical Collapse Pressure:

Safety Factor Against Buckling:

Input Parameters

• Internal Bore Diameter (inch)
• Depth of the Borehole below Ground Surface (ft)
• Unit Weight of Fluid in Borehole (lb/ft3)
• Unit Weight of Soil (lb/ft3)
• Internal Friction Angle of Soil (degree)
• Pipe Outside Diameter (inch)
• Standard Dimensions Ratio
• Percent of Ovality
• Apparent Modulus of Elasticity (psi)
• Poisson’s Ratio
• Radius of Curvature (ft)
• Live Load (lb/ft2)

Outputs/Reports

• Earth Pressure Coefficient
• Arching Factor
• External Earth Pressure (psi)Net External Pressure (psi)
• External Pressure Deflection (percent)
• Buoyant Deflection (percent)
• Deflection due to Reissner Effect (percent)
• Ovality Compensation Factor (percent)
• Critical Collapse Pressure (No Safety Factor) (percent)
• Safety Factor Against Buckling

Related Links

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