The only soil data available are in the borehole log (two sheets) provided. Assume the unit weights of all soil layers to be 18 kN/m3 and that the watertable is variable and can be up to the ground surface. Take unit weight of reinforced concrete = 25 kN/m3.Make use of the lecture notes to obtain any parameters and correlationformulae/ design Tables you need. The standard penetration test (SPT) blow counts (shown as N=….) for varioussoil layers are to be treated as N55 (corresponding to 55% energy ratio. Assume that incompressible bedrock exists below the bottom of theborehole.
You are required to carry out the following tasks, using Eurocode 7 Design Approach 1 procedures and safety factorsfor GEO limit state verification:
(i) Determine the size of an isolated square pad for column A1founded at 3 m depth and of thickness 0.3m.You must take into account all the actions(column forces, moments).
(ii) Check that, under the design pressure, the pad foundation settlement does not exceed 50 mm. If it does, then repeat the whole design task in step (i) above.
(iii) Calculate and plot pile design charts showing variation of design pile head resistance (kN) versus pile length (m), for the following trial diameters of a straight-shafted bored cast in-situ pile: 0.6m, 0.75m, 0.9m, 1.2m. Use your chart to determine the required pile length for column A1. Consider only column axial forces and ignore moments and shear forces.
