Seepage Analysis Tool — Bligh • Lane • Khosla
Online uplift, exit gradient, and piping checks with clear plots + section diagram (prototype)
Units: meters, % pressures, head in meters
Inputs
Total head causing seepage, H (m)
Soil type (for safe exit gradient)
Fine sand
Coarse sand
Shingle
Total floor length, b (m)
Floor specific gravity, Gs
Upstream pile depth, d1 (m)
Intermediate pile depth, d2 (m)
Downstream pile depth, d3 (m)
Distance b1 (u/s → intermediate) (m)
Distance b2 (intermediate → d/s) (m)
Floor thickness (uniform), t (m)
Bligh coefficient C (soil dependent)
Lane coefficient C1 (soil dependent)
Run analysis
Load sample
This prototype focuses on the classic 3-pile layout used in the references’ worked examples and can be extended to more configurations.
Results
Exit Gradient (Khosla)
—
—
Max uplift head (Khosla)
—
under floor
Bligh: L vs C·H
—
—
Lane: Lw vs C1·H
—
—
Plots
Section
Calculation steps
References
Bligh:
creep path + head loss proportional to creep length; safety by sufficient creep length.
Lane:
weighted creep (horizontal and vertical have different weight).
Khosla:
% pressures at key points, corrections (floor thickness, interference, slope), and exit gradient safety ranges.
Equations and tables are taken from the two PDFs you provided (see the cited pages/sections in those documents).