A soft to very soft silty clay layer 3 m thick exists between a layer of permeable clayey silty sand at top and a nearlyimpermeable layer of stiff silty clay at bottom. Oedometer tests were carried out on a sample of the soft clay 19mmthick. From the plot of ΔH versus log time, the value of time t100 (the time at 100% primary consolidation) was100 min. From the graph of e versus log σ' the compression index Cc was 0.32 and the void ratio ep at the end of theprimary consolidation was 0.72. Estimate the secondary compression of the silty clay layer that would occur fromtime of completion of the primary consolidation to 30 years of the load application in the field.

A soft to very soft silty clay layer 3 m thick exists between a layer of permeable clayey silty sand at top and a nearlyimpermeable layer of stiff silty clay at bottom. Oedometer tests were carried out on a sample of the soft clay 19mmthick. From the plot of ΔH versus log time, the value of time t100 (the time at 100% primary consolidation) was100 min. From the graph of e versus log σ' the compression index Cc was 0.32 and the void ratio ep at the end of theprimary consolidation was 0.72. Estimate the secondary compression of the silty clay layer that would occur fromtime of completion of the primary consolidation to 30 years of the load application in the field.

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 11.15P

See similar textbooks

Similar questions

11.15 The time for 65% consolidation of a 19-mm clay specimen (drained at top and bottom) in the laboratory is 10 minutes. How long will it take for a 4-m-thick clay layer in the field to undergo 40% consolidation under the same pressure increment? In the field, there is a rock layer at the bottom of the clay. 11.16 A 3.75 m clay layer in the field (drained on one side) is normally conso
A clay layer 5 m thick has double drainage. It was consolidated under a load of 127.5 kN/m2. The load is increased to 197.5 kN/m2. The coefficient of volume compressibility is 5.79 × 10^–4 m2/Kn and value of k = 1.6 × 10^–8 m/min. If the test sample is 2 cm thick and attains 100% consolidation in 24 hours, what is the time in days taken for 100% consolidation in the actual layer? Show diagram
The time for 75% consolidation of a 25 mm clay specimen (drained at top and bottom) in the laboratory is 22 minutes. How long will it take for a 6 m thick clay layer (same clay) in the field to undergo 55% consolidation under the same pressure increment? In the field, there is a rock layer at the bottom of the clay layer.
For a laboratory consolidation test on a clay specimen (drained on both sides), the followingresults were obtained. (7.5)Thickness of the clay layer = 25 mmP1= 100 kN/m2 e1= 0.81P2= 200 kN/m2 e2= 0.73Time for consolidation (t50) = 3.4 minDetermine the hydraulic conductivity of the clay for the loading range
Laboratory test on a 35 mm thick clay specimen drained just at the top show that 60% consolidation takes place 9.5 minutes. a) How long will it take for a similar clay layer in the field, 3,6 m thick, but drained at both the top and bottom, to undergo 60% consolidation? b) Find the time required for the clay layer in the field as described in part (a) above to reach 70% consolidation,
A clay stratum is 4.5 m thick and rests on a rock surface. The coefficient of consolidation of a sample of this clay was found to be 4.5 × 10–8 m2/s in the laboratory. Determine the probable period of time required for the clay stratum to undergo 50% of the ultimate settlement expected under a certain increment of pressure. a.1521 b.1026 c.1346 d.1333
A fine-grained (silty-clay) soil is required for the core of a rockfill dam. The permeability tests are performed on two types of soil. The diameter (D) of the specimen was 8 cm, length (L) between the measuring points was 15 cm. the following table shows the recorded data during the test for both the soils. Soil A B Head difference, h (cm) 12 15 Volume of water, V (cm3) 10 8 Time, t (sec) 300 350 Compute the hydraulic conductivity (k) by applying Darcy’s Law and select the best soil. Give reasons for the answer.
An oedometer test is performed on a 2 cm thick clay sample. After 5 minutes, 50% consolidation is reached. After how long a time in no. of days would the same degree of consolidation be achieved in the field where the clay layer is 3.70 m thick? Assume the sample and the clay layer have the same drainage boundary conditions (double drainage).Show Diagram a.234 b.119 c.564.3 d.17.15