Problem No. 12.C.1 @ Page 488 - 489Books: Principles of Geotechnical Engineering by Braja M. Das 8th Edition Consolidated-drained triaxial tests73 (kN/m²)(Ar); (kN/m²)150527275965350122545015805101800Figure 12.58Task 2: Loading the specimen through a specified stress pathA soil specimen is loaded along the stress path O (0, 0), P (250, 0), and A (675,1000) under drained conditions to reach point A close to the failure line estab-lished in Task 1 (Figure 12.58). Determine the combinations of confining pres-sure and deviator stresses applied to the triaxial specimen at 0, P, and A in orderto follow the stress path O-P-A.© Cengage Leaming 2014Failure lineStress path O-P-AO Cengage Learning 2014 Critical Thinking Problem12.C.1 A soil element in the field may go through various complicated stresspaths during the lifetime of a geotechnical structure. It is sometimes possibleto simulate these field conditions by advanced triaxial stress path testing,in which the axial and confining pressures are independently controlled andvaried to achieve a desired stress path in the p'-q space. This way, soilbehavior can be predicted under more realistic field conditions. In thisproblem, we will investigate the influence of stress paths in producing themost damaging strains in a granular material undergoing consolidateddrained triaxial testing. The following definitions of p' (mean normaleffective stress) and q (deviatoric stress) are used in this study (Schofieldand Wroth, 1968):p' =(o + o; + ơ;) = (o + 203), (note: o'; = o', for triaxial tests)q = 01 – 03Task 1: Establishing the failure line in the p' – q spaceThe following table shows the results of a series of consolidated-drained triaxialtests on a medium dense granular soil. Draw the stress paths for each test in thep'-q space. Also, establish the failure line going through the origin and con-necting the failure points (p/, q).

a) The deviator stress at failure , ∆σdf = σ'1 - σ'3…

Consolidated-drained triaxial tests 0z (kN/m²) (Ao d; (kN/m²) 150 527 275 965 350 1225 450 1580 510 1800 Figure 12.58 Task 2: Loading the specimen through a specified stress path A soil specimen is loaded along the stress path O (0, 0), P (250, 0), and A (675, 1000) under drained conditions to reach point A close to the failure line estab- lished in Task 1 (Figure 12.58). Determine the combinations of confining pres- sure and deviator stresses applied to the triaxial specimen at 0, P, and A in order to follow the stress path O-P-A. © Cengage Leaming 2014 Failure line Stress path O-P-A © Cengage Leaming 2014

Consolidated-drained triaxial tests 0z (kN/m²) (Ao d; (kN/m²) 150 527 275 965 350 1225 450 1580 510 1800 Figure 12.58 Task 2: Loading the specimen through a specified stress path A soil specimen is loaded along the stress path O (0, 0), P (250, 0), and A (675, 1000) under drained conditions to reach point A close to the failure line estab- lished in Task 1 (Figure 12.58). Determine the combinations of confining pres- sure and deviator stresses applied to the triaxial specimen at 0, P, and A in order to follow the stress path O-P-A. © Cengage Leaming 2014 Failure line Stress path O-P-A © Cengage Leaming 2014

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter12: Shear Strength Of Soil

Section: Chapter Questions

Problem 12.1CTP

See similar textbooks

Similar questions

A soil specimen is subjected to tri axial test. The soil specimen is cohesion less. If the shear stressthat causes failure is 335 KPa and the normal stress at failure is only 435 KPa, determine the following:1. Angle of shearing resistance.2. Angle that the failure plane measured from the major principal plane.3. Total axial stress at which failure is expected to occur.
Soil sample size is (21cm×21cm)
A soil specimen has an angle of shearing resistance of 28° and cohesion of 31kPa. The shearing stress on the failure plane is 65kPa. Which of the following most nearly gives the maximum normal stress to cause failure?
The diagram below shows a multi-layered soil, write an expression for the stress at each layer and the vertical total stress at depth z. (all symbols have their usual meaning)
Geotech engineering
Give me c, d&e answers only
4. The uniaxial compressive strength test is done on a cylindrical rock specimen with diameter of 60 mm and length of 120 mm. The load- deformation diagram of this specimen is shown on the following figure. Determine the uniaxial compressive strength and the secant Young modulus (E50) of this rock. 80000 70000 60000 50000 40000 30000 20000 10000 0.5 1 1.5 Deformation (mm) Load (N) 2.
2. Ten point load tests are carried out on cylindrical specimens of a sedimentary rock with 30 mm diameter, as shown in the figure. 50 mm The failure loads of these tests are equal to: 3.2, 4.1, 3, 3.8, 2.9, 4.2, 3.5, 3.6, 3.5 and 4 kiloNewtons. Determine Iyso of this rock. Predict the uniaxial compressive strength of this rock.
A 2 m thick clay is singly drained. A structure founded on the surface applied an average stress increase of 50 kPa to this clay layer. A piezometer is installed at the mid-depth of the clay layer. A. What would you expect the initial excess pore pressure reading on the piezometer to be immediately after application of load? B. C. The piezometer recorded a pore pressure of 25 kPa, 1-yr after the application of the stress. What would you expect it to read 2 years later? What is the coefficient of consolidation of this clay in cm²/s?
A soil sample is subjected to major principal stress of 2 kg/cm² and minor principal stress of 1,1 kg/cm². Determine the normal and shear stress on a plane at 30° to the minor Principal stress?
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.
Q.64 In an unconfined compression test, a sample clay 100 mm and 50 mm in diameter fails under a load of 150 N at 10% strain. What is the shearing resistance taking into account the effect of change in cross-section of the sample? (a) 0.068 N/mm2 (c) 0.034 N/mm2 (b) 0.088 N/mm2 (d) 0.044 N/mm? Ans. (a)