(Solved): The value of X is 7 Figure 1 below shows the cross section of a sheet pile wall driven to a depth o ...

The value of X is 7

Figure 1 below shows the cross section of a sheet pile wall driven to a depth of \( 6 \mathrm{~m} \) into a permeable sand layer of \( 13.5 \mathrm{~m} \) thickness lying on an impermeable soil layer. The water on one side of the wall is at a height of \( 4.5 \) \( \mathrm{m} \), while on the other side pumps maintain the water level at ground level. Assuming that the unit weight of water is equal to \( 10 \mathrm{kN} / \mathrm{m}^{3} \) : a) Sketch the flow net for the water levels shown assuming the soil is hydraulically isotropic. (8.marks) b) Determine the flow rate under the wall in \( \mathrm{m}^{3} / \mathrm{s} \) per meter run. The permeability of the soil is \( \mathrm{k}=\mathrm{X} \cdot 10^{-3} \mathrm{~m} / \mathrm{s} \) in every direction. (6 marks) c) Calculate the pore water pressures at point \( A \) just under the toe of the sheet piled wall. (6 marks)