A sandy aquifer which underlies saturated stiff clay is under artesian water pressure.Water in the exploratory drill hole rose to a height of 9 meters. An open excavation was made in the saturated stiff clay for a landfill which lies above the sandy aquifer.Assuming the factor of safety is 1.5. What will be thickness of the stiff clay layer from the bottom of the excavation to the top of the sandy aquifer to ensure that the bottom of the excavation will not heave?(The unit weight of clay layer is 18.5KN/m3

A sandy aquifer which underlies saturated stiff clay is under artesian water pressure.Water in the exploratory drill hole rose to a height of 9 meters. An open excavation was made in the saturated stiff clay for a landfill which lies above the sandy aquifer.Assuming the factor of safety is 1.5. What will be thickness of the stiff clay layer from the bottom of the excavation to the top of the sandy aquifer to ensure that the bottom of the excavation will not heave?(The unit weight of clay layer is 18.5KN/m3

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 16.10P

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1 2-meter clay layer ( e= 0.96, Gs = 2.67, Cc = 0.308) is overlain with 3-meter-thick sand layer (e = 0.84, G=2.8).The water table is at the interface of the sand and clay layer. If a 2-meter-thick landfill (y= 17.3 kN/m3) is placed over the existing ground surface, compute the consolidation settlement (in mm). of the clay layer. Hint: use the land fill's resulting pressure on the ground surface as the stress increase.
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