A permanent load of 2500kN and an imposed load of 1250 kN are to be supported on a square pad foundation at a depth of 1.0 m in a deposit of gravelly sand extending from the surface to a depth of 6.0 m. A layer of clay 2.0 m thick lies immediately below the sand. The water table may rise to foundation level. The unit weight of the sand above the water table is 17 kN/m3 and below the water table the saturated unit weight is 20 kN/m3. Characteristic values of the shear strength parameters for the sand are c = 0 and ϕ = 38 . The coefficient of volume compressibility for the clay is 0.15m2/MN. It is specified that the long term settlement of the foundation due to consolidation of the clay should not exceed 20 mm. Using the Working Stress Design Approach with Fs = 2.5, determine the foundation size to safeguard against bearing capacity failure and excessive settlement
A permanent load of 2500kN and an imposed load of 1250 kN are to be supported on a
square pad foundation at a depth of 1.0 m in a deposit of gravelly sand extending from the
surface to a depth of 6.0 m. A layer of clay 2.0 m thick lies immediately below the sand.
The water table may rise to foundation level. The unit weight of the sand above the water
table is 17 kN/m3 and below the water table the saturated unit weight is 20 kN/m3.
Characteristic values of the shear strength parameters for the sand are c = 0 and ϕ = 38 .
The coefficient of volume compressibility for the clay is 0.15m2/MN. It is specified that
the long term settlement of the foundation due to consolidation of the clay should not
exceed 20 mm. Using the Working Stress Design Approach with Fs = 2.5, determine the
foundation size to safeguard against bearing capacity failure and excessive settlement
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