A new retail store is being planned for a site that contains 20 feet of soft clay underlain by impermeable bedrock. The coefficient of consolidation for the clay is 0.25 ft /day. The groundwater table is at the ground surface. Ten feet of sandy fill with a total unit weight of 120 pcf is placed at the site as a working platform for construction. Determine the excess pore pressure at a depth of 5 feet above the bedrock three years after the fill is placed. 3.

In a reclamation project, the middle of a clay layer is under an initial effective vertical stress of 200 kPa and initial void The clay is ratio (eo) of 0.90. overconsolidated with OCR of 1.4, compression index of 0.34 and expansion index of 0.07. With an applied load of 299 kPa, what will be the final void ratio (e1) for the clay?

A surcharge and sand drain installation is proposed for an airport project to accelerate the consolidation of a thick deposit of fine-grained soil underlying the construction area. The plan is to install sand drains 1.5 ft in diameter at a staggered spacing so that each sand drain will handle a plan area 15 ft in diameter. Laboratory tests indicate that the coefficient of consolidation for horizontal drainage of the soil is 0.5 ft2/day. Computations indicate that the surcharge load will cause an eventual settlement of 12 in. How long a period will be required for 90 percent of this settlement to take place?

Estimate the total consolidation settlement (primary & secondary) after 2 years and 3 months after the completion of primary consolidation settlement of an over consolidated clay layer under the bridge pier as shown below. The pier's dimensions are (2 m x 3 m). Use Yw= 10 kN/m³ and note that the time for completion the primary consolidation is 3 years. | Qo= 960 kN G.W.L 1m Sand Ya=16.5 kN/m 2 m Ysat = 18 kN/m³ Silty Sand Ya=17.5 kN/m 3 m Ysat = 18.5 kN/m3 Clay Ya=20 kN/m , Ysat = 21 kN/m3 e, = 0.6 , Ae=0.04 , o= 78.3 kN/m2 4 m Cc= 0.4, Cs= 0.1, Ca= 0.02