Two identically clay samples of the same size designated as A and B are subjected to consolidation under identical conditions. Drainage takes place through one face in sample A and through both the faces in sample B. 50% consolidation of sample A occurs in 10 minutes.

Two identically clay samples of the same size designated as A and B are subjected to consolidation under identical conditions. Drainage takes place through one face in sample A and through both the faces in sample B. 50% consolidation of sample A occurs in 10 minutes.

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter11: Compressibility Of Soil

Section: Chapter Questions

Problem 11.9P

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The laboratory consolidation test is conducted on a clay sample. The following data results were obtained P1 =55 kPa P2 = 130 kPa e1= 0.95 e2= 0.80 Thickness of the sample of clay= 35mm Time for 50% consolidation = 3.0 min Tv= 0.197 a. Find the coefficient of volume compressibility b. Determine the coefficient of consolidation if a sample of clay was drained on both sides c. Compute the hydraulic conductivity of the clay
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In a consolidated drained tri-axial text on a normally consolidated clay soil, a deviator of 152 kPa was required to fail the sample when the confining pressure was 70 kPa. A. What was the angle of shearing resistance? B. Suppose that after consolidation under the 70 kPa confining pressure, the sample is placed in an unconfined compression apparatus and tested. Determine the resulting shear strength.
ANSWER MUST BE: (a) t50 = 8.37 years, (b) t90 = 35.96 years, (c) U ≈ 17%, (d) U ≈ 39% A clay specimen was tested in a laboratory consolidation device, whichwas 12.7 mm (½ in.) thick and the top and the bottom boundaries weredrained. A 50% consolidation time on the specimen was obtained as28.4 minutes. Determine the following:(a) Time for 50% consolidation in the field with this soil with a 2.5 mthickness where only the top layer is drained (b) Time for 90% consolidation in the field with this soil with a 2.5 mthickness where only the top layer is drained (c) For the same field condition above, at the end of 1 year after theplacement of load, how much primary consolidation settlementoccurs relative to its final amount of the settlement? (d) The same question as in (c), but at the end of 5 years
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answer 10 onl 1. When consolidation of a saturated soil sample occurs, the degree of saturation A.Increases B.Decreases C.Remains constant D.May increase or decrease 2. The process opposite to consolidation is called swelling, which involves an increase in the volume of the voids due to the water content A.Decreasing B.Increasing C.Equalize D. None of the above 3. OC: is refer to A. An over consolidation ratio as the ratio of the preconsolidation pressure to the present vertical effective stress. (B. A normally consolidated clay is defined as a clay that has a present (in situ) vertical effective stress oo' equal to its preconsolidation pressure oc C. An overconsolidated clay is defined as a clay that has a present vertical effective stress of less than its preconsolidation pressure D. None of the above Сс 4. Coefficient of consolidation of a soil is affected by A.Compressibility B.Permeability C.Both compressibility and permeability D.None of the above 5. The shear strength of a soil…
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