Footings Supported on Layered Soils

SuB is the undrained shear strength of the lower soil stratum H is the thickness of upper layer in two-layer system D is the depth of widest cross-sectional area 

The spud can consists of two independent parts the slab foundation and the conical tip. 

The bearing capacity of a ring is calculated as the difference between the bearing capacities of two subsequent circular foundations. 

The ultimate bearing capacity of the spud can is the sum of the bearing capacities of foundation parts. 

Punching shear parameter. (After Hanna, A.M. and Meyerhof, G.G., Canadian Geotech. /., 17, 300-303, 1980. Reprinted with permission of Canadian Geotechnical Journal.) 

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