A square footing is to carry a concentric wind-load related uplift force. The footing width, depth...

 

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A square footing is to carry a concentric wind-load related uplift force. The footing width, depth of water table and layer-wise soil properties are tabulated below. The footing base will be 400 mm thick, the square column that would transmit the uplift force will be 400 mm wide; both constructed with reinforced cement concrete with 25 kN/m unit weight. i. Construct a free body diagram assuming the failure surface to be vertical that runs along the footing perimeter and derive a relationship for the uplift force and average undrained shear strength. ii. Assuming the undrained shear strength to depend on effective vertical stress and overconsolidation ratio according to s,/o, = 0.25x OCR8 and the applicable factor of safety to be 2.5, find the ultimate and allowable uplift load that the footing is expected to carry. 16 9. 19 1.14 A square footing is to carry a concentric wind-load related uplift force. The footing width, depth of water table and layer-wise soil properties are tabulated below. The footing base will be 400 mm thick, the square column that would transmit the uplift force will be 400 mm wide; both constructed with reinforced cement concrete with 25 kN/m unit weight. i. Construct a free body diagram assuming the failure surface to be vertical that runs along the footing perimeter and derive a relationship for the uplift force and average undrained shear strength. ii. Assuming the undrained shear strength to depend on effective vertical stress and overconsolidation ratio according to s,/o, = 0.25x OCR8 and the applicable factor of safety to be 2.5, find the ultimate and allowable uplift load that the footing is expected to carry. 16 9. 19 1.14

Answer rating: 100% (QA)

Solution Arsh Giren DESIGN OF ISOLATED FOOTING 1 Column sze 400 mm X 400 mm P foctored load 2oo KN ... View the full answer