Question4: The ground condition is shown below along with the material properties for a building site. Design a footing based on bearing capacity equations for a column that will carry 800 kN of load.

QUESTION 4                                                                                                               [30 MARKS]

The ground condition is shown below along with the material properties for a building site. Design a footing based on bearing capacity equations for a column that will carry 800 kN of load. Assume a factor of safety of 2.0.

Hint: Assume a footing size and footing depth. Calculate the design bearing pressure below the footing because of the column load. Calculate the ultimate bearing capacity and then the safe bearing capacity. The safe bearing capacity needs to be greater than design bearing pressure. If not try a bigger footing size.

Soil properties

Light brown clay

γ = 18 kN/m³

c = 9 kPa

φ = 29⁰

Stiff grey clay

γ = 16 kN/m³

c = 10 kPa

φ = 30⁰