Symbols and Notations γ, γm = Unit weight, bulk unit weight, moist unit weight γd = Dry unit weight γsat = Saturated unit weight γb, γ' = Buoyant unit weight or effective unit weight γs = Unit weight of solids γw = Unit weight of water (equal to 9810 N/m3)
W = Total weight of soil
Ws = Weight of solid particles
Ww = Weight of water
V = Volume of soil
Vs = Volume of solid particles
Vv = Volume of voids
Vw = Volume of water
S = Degree of saturation
w = Water content or moisture content
G = Specific gravity of solid particles
The three-moment equation gives us the relation between the moments between any three points in a beam and their relative vertical distances or deviations. This method is widely used in finding the reactions in a continuous beam.
Consider three points on the beam loaded as shown.