At a construction site a 3 m thick clay layer is followed by a 4m thick gravel layer, which is resting on impervious rock. A load of 25 kN/m2 is applied suddenly at the surface. The saturated unit weights of the soils are 19 kN/ m3 and 20 kN/m3 for the clay and gravel layers, respectively. The watertable is at the surface. Draw diagrams showing variation, with depth, of total, neutral and effective stresses in the layers.

At a construction site a 3 m thick clay layer is followed by a 4m thick gravel layer, which is resting on impervious rock. A load of 25 kN/m2 is applied suddenly at the surface. The saturated unit weights of the soils are 19 kN/ m3 and 20 kN/m3 for the clay and gravel layers, respectively. The watertable is at the surface. Draw diagrams showing variation, with depth, of total, neutral and effective stresses in the layers.

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter8: Stresses In A Soil Mass

Section: Chapter Questions

Problem 8.10P: The soil profile at a site consists of 10 m of gravelly sand underlain by a soft clay layer. The...

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A 5.1 m thick clay soil with a current overburden pressure of 89 kPa is going to experience an additional stress of 89 kPa after a new structure is built. If it was determined that the clay is normally consolidated has an initial void ratio of 1.2, a recompression index of 0.07, and a compression index of 0.47. Determine the total amount of settlement that is expected to occur. Provide your answer in meters to 3 decimal places.
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The soil profile at a site consists of 10 m of gravelly sand underlain by a soft clay layer. The water table lies 1 m below the ground level. The moist and saturated unit weights of the gravelly sand are 17.0 kN/m3 and 20.0 kN/m3, respectively. Due to some ongoing construction work, it is proposed to lower the water table to 3 m below the ground level. What will be the change in the effective stress on top of the soft clay layer?
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