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Seismic Design (Pipeline) Calculator

Seismic Loading Analysis per ASCE 7 & ALA Guidelines

Pipeline Seismic Design Calculator
Evaluate pipeline response to seismic loading per ASCE 7 and ALA (American Lifelines Alliance) Guidelines. Calculates ground strain from wave propagation, axial and bending stresses, fault crossing strain, liquefaction potential, and provides pass/fail assessment per ALA criteria.

Pipe Properties

in
in
psi
psig

Seismic Parameters

g

From ASCE 7 or USGS hazard maps (475-year return period)

cm/s

PGV ≈ PGA(g) × 100 for soft soil (approximate)

Fault Crossing (optional)

ft

0 = no fault crossing. Typical: 1–10 ft for active faults.

°

90° = perpendicular crossing (worst for bending)

Soil & Burial Conditions

ft
ft

Used for liquefaction assessment. 0 = at surface.

Understanding Pipeline Seismic Design

Wave Propagation
Seismic waves induce ground strain that is transmitted to buried pipelines. The ground strain depends on peak ground velocity and apparent wave propagation velocity.
Permanent Ground Deformation:
Fault crossing, lateral spreading, and landslide impose large displacements that require strain-based design rather than stress-based limits.
When to Use:
Pipeline routes in seismically active areas, fault crossings, areas with liquefaction potential, and any pipeline system requiring ASCE 7 or ALA compliance.

Formula

εg = PGV / Cs
εg = Ground strain (in/in)
PGV = Peak ground velocity (in/s)
Cs = Apparent wave propagation velocity (in/s)
σa = E × εg (axial stress)

Standards & References

  • ASCE 7
    Minimum Design Loads — Seismic Parameters
  • ALA Guidelines
    Seismic Guidelines for Water Pipelines (2005)
  • ASCE-TCLEE
    Pipeline Design for Seismic & Geohazards
  • PRCI
    Pipeline Research Council International seismic guidelines

Engineering Notes

  • Wave propagation: Ground strain from body/surface waves is typically < 0.1% for moderate earthquakes
  • Fault crossing: Permanent displacement can cause 1–5% strain; requires strain-based design
  • Liquefaction: Saturated loose sand (water table < 30 ft) is susceptible at PGA > 0.1g
  • Butt-welded steel: Best performance; can accommodate > 2% strain before failure
  • Site Class D/E: Soft soils amplify ground motion and increase seismic demand