A site associated with an excavation project is underlain by a 6m thick sand layer with unit weights = 18 and 20 kN/m³. Below the sand layer lies a 6m thick clay layer with unit weights = 19 and 22 kN/m³, void ratio=1.3. The water table is located at the ground surface. Rock lies below the clay layer. The consolidation parameters obtained from testing a sample obtained from a depth of 9m are: coefficient of consolidation = 0.018 m²/day, compression index=0.3, recompression index = 0.02. A dewatering operation will cause the water table to drop 5m and remain there throughout the project. Calculate the average degree of consolidation of the clay layer 100 days after the onset of dewatering. Express your answer in percent but write only the numeric answer in the text box.

A site associated with an excavation project is underlain by a 6m thick sand layer with unit weights = 18 and 20 kN/m³. Below the sand layer lies a 6m thick clay layer with unit weights = 19 and 22 kN/m³, void ratio=1.3. The water table is located at the ground surface. Rock lies below the clay layer. The consolidation parameters obtained from testing a sample obtained from a depth of 9m are: coefficient of consolidation = 0.018 m²/day, compression index=0.3, recompression index = 0.02. A dewatering operation will cause the water table to drop 5m and remain there throughout the project. Calculate the average degree of consolidation of the clay layer 100 days after the onset of dewatering. Express your answer in percent but write only the numeric answer in the text box.

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 11.16P

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