QI- An embankment is to be constructed over a layer of soft clay 16 m thick as shown in figure 1. Construction the embankment will increase the total vertical stress in the clay layer by 110 kPa. The design requirement is that all but 25 mm of the settlement due to consolidation of the clay layer will have taken place after 6 months. Determine: A. The spacing in best pattern of 500 mm diameter sand drains to achieve the above requirement. B. Which is the best, the use of sand drains or pre-fabricated drains? Why? (25%) Embankment Clay Cy = 4.7 m?/ year Ch 7.9 m2/ year my= 0.25 m2/ MN 16 m Sand Figure (1).

QI- An embankment is to be constructed over a layer of soft clay 16 m thick as shown in figure 1. Construction the embankment will increase the total vertical stress in the clay layer by 110 kPa. The design requirement is that all but 25 mm of the settlement due to consolidation of the clay layer will have taken place after 6 months. Determine: A. The spacing in best pattern of 500 mm diameter sand drains to achieve the above requirement. B. Which is the best, the use of sand drains or pre-fabricated drains? Why? (25%) Embankment Clay Cy = 4.7 m?/ year Ch 7.9 m2/ year my= 0.25 m2/ MN 16 m Sand Figure (1).

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter3: Weight–volume Relationships

Section: Chapter Questions

Problem 3.24P

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