Representative samples of a layer of silty clay, 5m thick, were tested in a consolidometer and the following results were obtained: Initial void ratio eq=0.90 Preconsolidation Recompression index C,=0.03 Compression insex Ce=0.27 stress o'c-120kN/m² Estimate the consolidation settlement if the present average overburden stress of the layer o'o -70kN/m² and increase in average stress in the laver is 80kN/m².

Representative samples of a layer of silty clay, 5m thick, were tested in a consolidometer and the following results were obtained: Initial void ratio eq=0.90 Preconsolidation Recompression index C,=0.03 Compression insex Ce=0.27 stress o'c-120kN/m² Estimate the consolidation settlement if the present average overburden stress of the layer o'o -70kN/m² and increase in average stress in the laver is 80kN/m².

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 11.12P

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2. A normally consolidated clay layer, 3 m thick, has the following properties: Initial void ratio, e 0.8 Compression index, Cc = 0.25 Average effective pressure, o'o= 125 Kpa Expected pre ssure increase, Aơ = 45 Kpa Secondary compre ssion index, Ca= 0.02 Time of completion of primary settlement = 1.5years What is the total settlement of the clay layer five ye ars afterthe completion of the primary se ttle ment?
Given the following data for the normally consolidated clay layer in the field. Compute the primary consolidation settlement. Thickness of clay layer= 3.0m Cc= 0.30 e= 0.70 Overburden pressure= 250 Kpa ΔP= 46 kPa Cα= 0.022
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q21 A bed consists of compressible clay of 4 m thickness with pervious sand on top and impervious rock at the bottom. In a consolidation test on an undisturbed specimen of clay from this deposit 90% settlement was reached in 4 hours. The specimen was 20 mm thick. The time for the building founded over this deposit to reach 90% of its final settlement will be (a) 91 years (с) 73 years (b) 82 years (d) 64 years
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