5. Based on one-dimensional consolidation test results on a clay, the coefficient ofconsolidation for a given pressure range was obtained as 9x 10-3 mm²/s. In the field, there is a 4m-thick layer of the same clay with one-way drainage. Based on the assumption that a uniformsurcharge of 90 kN/m² was to be applied instantaneously, the total consolidation settlement wasestimated to be 160 mm.However, during the construction, the loading was gradual; the resulting surcharge can beapproximated asEstimate the settlement at(a) t-45 day and(b) 150 days.kN909 (m²) = 90 tkN9 (2) = 90१for t ≤90 daysfor t>90 days

To estimate the settlement at different time intervals during gradual loading, you can use the…

5. Based on one-dimensional consolidation test results on a clay, the coefficient of consolidation for a given pressure range was obtained as 9x 10-3 mm²/s. In the field, there is a 4 m-thick layer of the same clay with one-way drainage. Based on the assumption that a uniform surcharge of 90 kN/m2 was to be applied instantaneously, the total consolidation settlement was estimated to be 160 mm. However, during the construction, the loading was gradual; the resulting surcharge can be approximated as Estimate the settlement at (a) t-45 day and (b) 150 days. kN 90 a(m²) = 90t kN 9 (m²) = 90 for t ≤90 days for t > 90 days

5. Based on one-dimensional consolidation test results on a clay, the coefficient of consolidation for a given pressure range was obtained as 9x 10-3 mm²/s. In the field, there is a 4 m-thick layer of the same clay with one-way drainage. Based on the assumption that a uniform surcharge of 90 kN/m2 was to be applied instantaneously, the total consolidation settlement was estimated to be 160 mm. However, during the construction, the loading was gradual; the resulting surcharge can be approximated as Estimate the settlement at (a) t-45 day and (b) 150 days. kN 90 a(m²) = 90t kN 9 (m²) = 90 for t ≤90 days for t > 90 days

Principles of Foundation Engineering (MindTap Course List)

8th Edition

ISBN:9781305081550

Author:Braja M. Das

Publisher:Braja M. Das

Chapter2: Geotechnical Properties Of Soil

Section: Chapter Questions

Problem 2.19P

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Similar questions

An oedometer test on a saturated clay soil gave the following results: Cc = 0.2 and Cs = 0.04. The in-situ vertical effective stress in the field is 130 kPa. A building foundation will increase the vertical stress in the center of the clay by 150 kPa. The thickness of the clay layer is 2 m and its water content is 28%. Calculate the primary consolidation settlement of the clay layer in the field if: a). OCR = 4.5; b). OCR = 1.5.
The laboratory consolidation data for an undisturbed clay specimen are as follows: e1 = 1.12 P₁ = 90 kPa e2 = 0.90 P2 = 450 kPa 1. Compute the value of the compression index. 2. Compute the value of the swell index assuming it is equal to 1/6 the value of the compression index. 3. Compute the void ratio for a pressure of 600 kPa. 4. Compute the coefficient of compressibility. 5. Compute the value of the coefficient of volume compressibility.
Refer to the soil profile shown in figure below. A laboratory consolidation test on the clay gave the results: o'c = 100 kPa Cc = 0.4 Cs = 0.2Cc If the average effective stress on the clay layer increases by 60 kN/m², what would be the total consolidation settlement in cm. Dry sand; e = 0.55 G,= 2.66: Sand G₂ = 2.66 e = 0.48. Clay w 34.78% G₂ = 2.74 Rock 1.5 m. 5 m Water table;
A 75 mm diameter clay specimen was consolidated in an oedometer under 200 kPa. At the end of consolidation, the void ratio is 0.863 and the specimen thickness is 18.51 mm. When the stress increment of 200 was added to the current vertical stress of 200 kPa, the specimen consolidated to a thickness of 17.56 mm. Assuming that the clay was normally consolidated under the vertical stress of 200 kPa, find the a) coefficient of volume compressibility in (MPa)^-1 and rounded to the 3rd decimal place.b) and the compression index of the clay rounded to the 2nd decimal place.
Q.4(a)(i) A laboratory consolidation test on a normally consolidated clay showed the following results: Load, 3( kN/m²) 140 212 Void ratio, e 0.92 0.86 The specimen tested was 25.4 mm in thickness and drained on both sides. The time required for the specimen to reach 50% consolidation was 4.5 min. A similar clay layer in the field 2.8 m thick and drained on both sides is subjected to a similar increase in average effective pressure (i.e. 5o = 140 kN/m² and Jo + 40 = - 212 kN/m²). Determine (a) the expected maximum primary consolidation settlement in the field. (b) the time required for the total settlement in the field to reach 40 mm. [Assume uniform initial increase in excess pore water pressure with depth]
The water content of a sample of saturated soil at a mean effective stress of 10 kPa is 85%. The sample was isotropically consolidated with a mean effective stress of 150 kPa. At the end of the consolidation, the water content was 50%. The sample was then isotropically unloaded to a mean effective stress of 100 kPa, and the water content increased by 1%. Given: Gs = 2.7, o'cs = 25°. a) Calculate and K. 10 b) Determine the failure stresses (p'f and gf) under CU test and CD test for the conditions.
Refer to the soil profile shown in Figure P2.12. The clay is normally consolidated. A laboratory consolidation test on the clay gave the results: If the average effective stress on the clay layer increase by 50 kN/m2.a. What would be the total consolidation settlement?b. If Cv = 9.36 x 10-4 cm2/sec, how long will it take for half the consolidation settlement to take place?
3. A consolidated undrained test on a normally consolidated clay yielded the following results: 7.2 psi Pore pressure: Chamber confining pressure: 15 psi 12 psi Calculate the consolidated-undrained friction angle and the drained friction angle. Deviator stress at failure:
The laboratory consolidation test is conducted on a clay sample. The following data results were obtained P1 =55 kPa P2 = 130 kPa e1= 0.95 e2= 0.80 Thickness of the sample of clay= 35mm Time for 50% consolidation = 3.0 min Tv= 0.197 a. Find the coefficient of volume compressibility b. Determine the coefficient of consolidation if a sample of clay was drained on both sides c. Compute the hydraulic conductivity of the clay
A fully saturated clay specimen is placed in a consolidometer and subjected to a loading of 200 kN/m². After some of time, it was found that the average pore pressure in the specimen was 70 kN/m². The percentage of consolidation reached by then was
A clay sample underwent a consolidation test in the lab. The clay specimen has drainage on both sides and a height of 25.4 mm. Assume that the clay sample's preconsolidation pressure was less than 150 kPa prior to the consolidation test. The void ratio was 0.96 when the applied effective vertical pressure was 150 kPa. When the vertical effective pressure increased from 150 to 220 kPa, the void ratio at the end of consolidation and compression was 0.88. It was discovered that the sample needed 3 minutes to consolidate by 30%. Following the consolidation test, a swelling/unloading test was conducted, in which the vertical effective stress was lowered from 220 to 150 kPa and the end-of-swelling void ratio was determined to be 0.9. Required a. The compression index of the clay b. The swelling index of the clay C. The height of the clay sample at the end of compression d. The coefficient of consolidation of the clay e. The final height of the clay sample at the end of swelling
Example 9.2: A clay soil, tested in a consolidometer, showed a decrease in void res •m 1.20 to 1.10 when the presure was increased from 0.25 to 0.50 kgflem?. Calculate to. efficient of compressibility (a) and the coefficient of volume compressibility (m). If t •ficient of consolidation (c,) determined in the test for the given stress increment u m?/year, calculate the coefficient of permeability in cm/s. If the sample tested at the site was taken from a clay layer 3.0 m in thickness, determin consolidation settlement resulting from the given stress increment. lution: