A rectangular footing of size 10 x 20 ft is founded at a depth of 6 ft below the ground surface in a homogeneous cohesionless soil having an angle of shearing resistance 0 = 35°. The water table is at a great depth. The unit weight of soil 7= 114 lb/ft3. Determine: (1) the net ultimate bearing capacity,
(2) the net allowable bearing pressure for FV = 3, and (3) the allowable load Qa the footing can carry.
Use Terzaghi’s theory. (Refer to Fig. Ex. 12.6)
Solution
Using Eq. (12.19) and Eq. (12.20) for c – 0, the net ultimate bearing capacity for a rectangular
footing is expressed as
