Issue 1 V1.08
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Loaded Rectangular Area - Westergaard's Layered Soil

More Cases

Below Rectangle Corner in Layered Soil

Notation and Units

Metric and Imperial Units

The above formulas may be used with both imperial and metric units. As with all calculations care must be taken to keep consistent units throughout with examples of units which should be adopted listed below:


  • B = width of foundation, ft or m
  • IW = Westergaard stress co-efficient
  • L = length of loaded area, ft or m
  • q = load per unit area, kip/ft2 or kN/m2
  • z = vertical distance from load to point of interest, ft or m
  • α & β = angle of interest, degrees
  • µs = Poisson’s ratio of the soil between the reinforcements
  • ∆σ = stress increase at point of interest, kip/ft2 or kPa