where sc, sg , sq are the shape factors (dimensionless).
For a strip footing, all of the shape factors equal 1.0, and Eq. 6.5 is the same as Eq. 6.1. For square
footings, the Terzaghi shape factors are sc = 1.3, sg = 0.8, and sq = 1.0, in which case Eq. 6.5 is the same
as Eq. 6.3. For rectangular footings of width B and length L, commonly used shape factors are: