For a given over consolidated clay: Specific gravity = 2.71 , Liquid limit = 45, In situ average effective over burden pressure = 120 kPa ,In situ void ratio = 0.80, Thickness of clay layer = 4m , ∆P = 40 kPa, Effective pressure at the mid – height of clay layer = 60 kPa , Swell index (Cs) = 1/5 Cc 1.) Compute the compression index. 2.) Compute the pre – consolidation pressure. 3) Compute the primary consolidation settlement.

For a given over consolidated clay: Specific gravity = 2.71 , Liquid limit = 45, In situ average effective over burden pressure = 120 kPa ,In situ void ratio = 0.80, Thickness of clay layer = 4m , ∆P = 40 kPa, Effective pressure at the mid – height of clay layer = 60 kPa , Swell index (Cs) = 1/5 Cc 1.) Compute the compression index. 2.) Compute the pre – consolidation pressure. 3) Compute the primary consolidation settlement.

Principles of Foundation Engineering (MindTap Course List)

8th Edition

ISBN:9781305081550

Author:Braja M. Das

Publisher:Braja M. Das

Chapter16: Soil Improvement And Ground Modification

Section: Chapter Questions

Problem 16.8P

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For a normally consolidated clay layer in the field, the following values are given:Thickness of clay layer = 8.5 ftVoid ratio ?? = 0.8Compression index ?? = 0.28Average effective pressure on the clay layer ??′ = 2650 lb ft2 ⁄∆?′ = 970 lb ft2 ⁄Secondary compression index ?? = 0.02What is the total consolidation settlement of the clay layer five years after the completionof primary consolidation settlement? (Note: Time for completion of primary settlement= 1.5 years.)
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