3- Following are the results of a laboratory consolidation test on a sample of undisturbed clay obtained from the field. Final height of specimen (in) Pressure, o' (lb/ft') 1 0.9917 1,000 0.9843 2,000 0.956 4,000 0.9142 8,000 16,000 32.000 0.8685 0.8228 The height of the specimen at the beginning of the test was 1.0 inch, and the diameter was 2.5 inches. The moist specimen weighed 0.31 lb and the water content was determined to be 19%. Estimate the compression index and the preconsolidation pressure from the e-log o' curve. (Plot in Excel) Given: Gs = 2.7.

3- Following are the results of a laboratory consolidation test on a sample of undisturbed clay obtained from the field. Final height of specimen (in) Pressure, o' (lb/ft') 1 0.9917 1,000 0.9843 2,000 0.956 4,000 0.9142 8,000 16,000 32.000 0.8685 0.8228 The height of the specimen at the beginning of the test was 1.0 inch, and the diameter was 2.5 inches. The moist specimen weighed 0.31 lb and the water content was determined to be 19%. Estimate the compression index and the preconsolidation pressure from the e-log o' curve. (Plot in Excel) Given: Gs = 2.7.

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 11.3P

See similar textbooks

Similar questions

Following are the results of a consolidation test on a sample of undisturbed clay obtained from the field. Pressure ơ' (kN/m²) Final Height of Specimen (mm) 24 10 23.78 20 23.30 50 22.22 100 20.58 200 19.04 400 17.52 800 16.31 17.75 The height of the specimen at the beginning of the test was 24 mm and the area of specimen was 50 cm? volume of specimen was 120 cm³. The mass of dry specimen was 180.4 g. Gs= 2.68. 1. Plot the e-log ơ' curve, 2. Using Casagrande's method, determine the preconsolidation pressure. 3. Calculate the compression index, Cc
The results of a laboratory consolidation test on a clay specimen are the following. Pressure, ir (lb/ft²) 500 1.000 2.000 4.000 8,000 16.000 Total height of specimen at end of consolidation (in.) 0.6947 0.6850 0.6705 0.6520 0.6358 0.6252 Given the initial height of specimen = 0.748 in.. G specimen = 95.2 g. and area of specimen = 4.91 in.²: a. Plot the e-log or curve = 2.68. mass of dry b. Determine the preconsolidation pressure c. Calculate the compression index, C.
1. Triaxial compression tests are done on quartzite rocks, the results are shown below. (0₁+03)/2 -964.25 14500 19575 23200 29000 43210 63075 psi (01-03)/2 964.25 14500 18850 21750 26100 35960 48575 psi Comment on the applicability of each of the Mohr-Coulomb, Griffith, and Hoek-Brown criteria for the testing results.
Question 2 The result presented in Table Q2a were obtained from a consolidated drained (CD) triaxial test on a normally consolidated clay sample of 75mm height x 38mm diameter tested at a confining pressure of 50 kPa. Table Q2a. CD triaxial test result Axial strain (%) 1 2 5 10 15 Applied force (kN) 0.01 0.03 0.05 0.08 0.10 Page 3 of 6 (a) Draw the Mohr circle for each stress state in the sample and the total stress path (TSP) throughout the test and determine the slope of the TSP to the horizontal.
10.9 A consolidation test on a sample of clay produced the following data: o:' (kPa) 8 16 32 64 128 256 512 1024 16 0.032 0.041 0.051 0.069 0.109 0.173 0.240 0.301 0.220 The initial void ratio of the sample was 1.21, and Ozo at the sample depth was 40 kPa. (a) Plot these data on an arithmetic diagram similar to that in Figure 10.10(a) (b) Plot these data on a semilogarithmic diagram similar to that in Figure 10.10(b). (c) Using Casagrande's method, find oc (d) Using Schmertmann's method, adjust the test results. (e) Determine Ccand Cr.
9. A consolidated drained test was carried out on a sandy clay under a cell pressure of 250 kPa. A constant back pressure of 120 kPa applied throughout the test. The dimensions of the sample were 76 mm x 38 mm. Addional test data recorded at failure were: Load transducer force = 368 N 3 Measured change in volume = 2.42 x 10 m³ Axial deformation = 2.05 mm Determine the major principal stress, o, at failure. (455 kPa)
A sandstone reservoir has an average thickness of 85 feet and a total volume of 7,650 acre-feet. A well was drilled and cored through the reservoir. A rock sample was sent to the laboratory and the following tests were run. The dry weight of the core sample was found to be 140 grams while the sample dimensions were 1.575 in. long and 1.960 in. in diameter. Assuming the compressibility at 4,500 psi is the average compressibility in the reservoir, how much subsidence occurs when the reservoir pressure declines from 5,500 psi to 3,500 psi? What is sample pore volume and porosity? Sandstone density is 2.65 g/cc. Pressure, psi Cumulative pore volume change (-cc) 1000 0.122 2000 0.162 3000 0.196 4000 0.224 5000 0.25 6000 0.273 7000 0.298 8000 0.315
The following results were obtained from a liquid limit test on a clay using the Casagrande cup device. Number of blows Moisture content (%) 6 12 20 28 32 52.5 47.1 43.2 38.6 37.0 a) Determine the liquid limit b) If the natural water content is 38% and the plastic limit is 23%, calculate the liquidity index. c) Would you expect a brittle failure? WHY?
Part #2 Effective Stress (kPa) Void Ratio (%) The following are the results of laboratory consolidation test conducted on clayey soil sample. Determine, graphically, the compression and recompression indices, Cc, C, of this soil. Using Casagrande's method, determine graphically the preconsolidation pressure. 0.891 54 0.866 107 0.841 214 0.802 429 0.737 858 0.653 1716 0.560 3432 0.467
ANSWER MUST BE: (a) t50 = 8.37 years, (b) t90 = 35.96 years, (c) U ≈ 17%, (d) U ≈ 39% A clay specimen was tested in a laboratory consolidation device, whichwas 12.7 mm (½ in.) thick and the top and the bottom boundaries weredrained. A 50% consolidation time on the specimen was obtained as28.4 minutes. Determine the following:(a) Time for 50% consolidation in the field with this soil with a 2.5 mthickness where only the top layer is drained (b) Time for 90% consolidation in the field with this soil with a 2.5 mthickness where only the top layer is drained (c) For the same field condition above, at the end of 1 year after theplacement of load, how much primary consolidation settlementoccurs relative to its final amount of the settlement? (d) The same question as in (c), but at the end of 5 years
Table 2.A consolidation test data An oedometer test is conducted for a soil sample.The sample is consolidated under vertical stress of 50 kPa. The Time (min) Dial gauge reading (mm) 194 0.01 0.02 193 0.05 190.5 oedometer test finished at 144 min and 0.1 186.5 data are given in Table I. Average thickness of the sample is 20 mm. Predict the coefficient of 0.2 181 0.5 173 1 168 2 164.5 consolidation (c, in mm?/min) using Casagrande log t method and Taylor square root of t method. Please use the empty graphical papers. 5 161.5 10 160 20 158.5 50 156.9 100 155.7 144 155.1
Can TRIAXIAL TESTS be performed on sand samples? Briefly explain. The results of an undrained triaxial test on a clay soil sample are given in table below Cell Pressure (kN/m2) 200 400 600 Additional Axial Load at Failure (N) 342 388 465 Each sample, originally 76mm long and 38mm in diameter, experienced a vertical deformation of 5.1mm. Evaluate the stress at failure for each cell pressure given in table above. Draw Mohr Circles and determine the shear strength parameters of the soil.