Chapter 11, Problem 11.4P

A 10-m-thick layer of stiff saturated clay is underlain by a layer of sand (Figure 9.28). The sand is under artesian pressure. A 5.75-m-deep cut is made in the clay. Determine the factor of safety against heaving at point A.

Water is flowing vertically upward in a sand with a saturated unit weight of 20 kN/m3. At what gradient will quick conditions occur?

A 450 kN force is transmitted by a column footing onto the surface through a square footing 1.5 m on a side. Assuming that the force exerted on the underlying soil formation spreads on 2 vertical to 1 horizontal, evaluate the pressure, in kPa exerted in footing on a soil 2.7 m below it.

Why is the passive soil pressure coefficient greater than 1?

A 10 m x 6 m mat foundation is placed at 2.0 m depth in sand where the average value of N60 is 23. Determine the allowable net pressure that would limit the settlement to 75 mm, using the following equations.

Compare the effect of surface loading on retained soil side on the lateral pressure behind retaining wall by assuming a uniformly distributed load of 20 kPa on the top of the soil behind the retaining wall. The soil properties are: c' = 0. φ'= 30°, γ = 19 kN/m3 and the height of retaining wall on active side is 6m.​Your answer should be in table form showing lateral pressure with and without superimposed loading, and the percent increase/decrease in total pressure at different depths.

1. The following is a sketch of the proposed embankment, calculate the addition of vertical stress (Bousinesq method / graph below) at the depths of points A and B. Assume the unit weight of the soil stockpile = 20 kN / m3. 2. Calculate the added vertical stress at points A and B as deep as Z = 8 m, under the rectangular load

Calculate the active earth pressure coefficient for the backfill soil using both the Rankineand Coulomb Earth Pressure theories. Is there a significant difference in the two Kavalues?

A site is underlain by a soil that has a unit weight of 18.7 kN/m3above the groundwater table and 19.9 kN/m3below. The groundwater table is located at a depth of 3.5 m below the ground surface. Compute the a) total vertical stress, b) pore water pressure, and c) effective vertical stress at the following depths below the ground surface: 2.2 m (Point A), 4.0 m (Point B), 6.0 m (Point C), d) draw a sketch and show the points( A, B, C) on the sketch.