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]

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]

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter10: Shear Strength Of Soil

Section: Chapter Questions

Problem 10.23P

See similar textbooks

Similar questions

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.
Please give me right solution according to the question. In a triaxial test on a saturated clay, the sample was consolidated under a cell pressure of 160 kPa. After consolidation the cell pressure was increased to 350 kPa, and the sample was then failed under undrained condition. If the shear strength parameters of the soil are c’ = 15.2 kPa, ϕ’ = 26°, B = 1, Af = 0.27, determine the pore pressure at the failure.
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:
A consolidated drained (CD) triaxial test was carried out on a normally consolidated clay. The specimen was consolidated under a cell pressure of 100 kPa and back pressure of 30 kPa. The axial deviatoric stress was increased very slowly to failure, so that there was no excess pore water pressure developed during the shearing. The specimen failed under a deviatoric stress of 130 kPa. The back pressure of 30 kPa was maintained throughout the test. (i) What is the friction angle in terms of effective stresses? (ii) What are the shear stress and normal stress acting on the failure plane? Solution fast please
5. A consolidated, undrained triaxial test is being caried out on a normally consolidated clay where c = 0 and 41= 26'. The triaxial specimen was consolidated under a cell pressure of 300 kPa and backpressure of 80 kPa. Skempton's A parameter at failure is estimated to be 0.80. The drainage valve has since been dosed and the vertical deviator stress increased to failure. What would be the deviator stress and pore water pressure at failure?
A CU triaxial test was carried out on a silty clay that was isotopically consolidated using a cell pressure of 125 kPa. The following data were obtained: Axial load (kPa) 0 5.5 11.0 24.5 28.5 35.0 50.5 85.0 105.0 120.8 Axial strain, E₁ (%) 0 0.05 0.12 0.29 0.38 0.56 1.08 2.43 4.02 9.15 Au (kPa) 0 4.0 8.6 19.1 29.3 34.8 41.0 49.7 55.8 59.0 (a) Plot the deviatoric stress vs. axial strain and excess porewater pressure vs. axial strain, respectively. (b) Determine the undrained shear strength (su). (Note: we assume that the sample reaches failure). (c) Determine the total principal stresses (0₁,03) and the effective principal stresses (0₁, 03') at the failure, respectively.
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.
A consolidated-undrained triaxial test was conducted on a saturated, normally consolidated clay. The test results are 03-13 lb/in2 01(failure) = 32 lb/in² Pore pressure at failure = u = 5.5 lb/in². Determine c, d, c', and '
A consolidated drained (CD) triaxial test was carried out on a normally consolidated clay. The specimen was consolidated under a cell pressure of 100 kPa and back pressure of 30 kPa. The axial deviatoric stress was increased very slowly to failure, so that there was no excess pore water pressure developed during the shearing. The specimen failed under a deviatoric stress of 130 kPa. The back pressure of 30 kPa was maintained throughout the test. (1) What is the friction angle in terms of effective stresses? (ii) What are the shear stress and normal stress acting on the failure plane?
A given saturated clay is known to have effective strength parameters of c' = 10 kPa and = 28°. A sample of this clay was brought to failure quickly so that no dissipation of the pore water pressures %3D could occur. At failure it was known that o KPa, o = 10 KPa and = 20 kPa. %3D (a) Estimate the values of o, and oz at failure (b) Use the Mohr circle to illustrate the effective stress and total failure stress.