In a consolidation test, a fully saturated clay specimen of 20 mm thick drained from both sides reaches 50% degree of consolidation in 18 min. How long would it take an 8-m thick layer of clay under the same stress condition (drained from both sides) to reach the same degree of consolidation?

In a consolidation test, a fully saturated clay specimen of 20 mm thick drained from both sides reaches 50% degree of consolidation in 18 min. How long would it take an 8-m thick layer of clay under the same stress condition (drained from both sides) to reach the same degree of consolidation?

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter2: Geotechnical Properties Of Soil

Section: Chapter Questions

Problem 2.12P

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A 75 mm diameter clay specimen was consolidated in an oedometer under 200 kPa. At the end of consolidation, the void ratio is 0.863 and the specimen thickness is 18.51 mm. When the stress increment of 200 was added to the current vertical stress of 200 kPa, the specimen consolidated to a thickness of 17.56 mm. Assuming that the clay was normally consolidated under the vertical stress of 200 kPa, find the a) coefficient of volume compressibility in (MPa)^-1 and rounded to the 3rd decimal place.b) and the compression index of the clay rounded to the 2nd decimal place.
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A 6 foot thick clay layer is determined to have the consolidation properties shown below. If the average in-situ stress is 500 psf and the preconsolidation stress is 1,000 psf, what is the settlement for this overconsolidated soil subjected to a stress increase of 2,000 psf.
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