Question

A braced cut 7 m deep and 4 m wide is to be installed where the water table is 0.5 m below the ground surface. The loose sand has a unit weight of 17.5 kN per cubic meter.

1. Determine whether a quick condition will take place at the base of the cut. Yes/No?

2. Assume a factor of safety of 2 and ignore any impervious layers below the cut. If a quicksand condition will happen, a proposed solution is to install much deeper sheet piling cut-off walls before the cut is to be done. What is the total length of the sheet piles?

Answer 1