A consolidated-drained tri-axial test was conducted on a normally consolidated clay. The results are as follows: 03 = 150 kN/m? (Aoa)f = 130 kN/m² Determine a. Angle of friction, o' b. Angle 0 that the failure plane makes with the major principal plane c. Find the normal stress o' and the shear stress tfon the failure plane

8. A soil particle is subjected to a maximum stress of 14.6 kPa and a minimum stress of -4.18 kPa. Determine the normal and the shear stresses on the plane of 0 = 50⁰ with respect to the major principal stresses and also determine the shear strength of soil particle. Answer: 3.6 kPa, 9.2 kPa, and 9.4 kPa.

1. Triaxial tests were carried out on 54-mm-diameter (NX core) intact rock specimens. The applied confining pressures and the principal stress differences at failure are summarised below5.210 Confining 0 5.0 10.0 15.0 20.0 25.0 pressure (MPa) Principal stress 59.5 87.5 116.0 139.5 167.5 192.5 difference (MPa) Plot o, against o, at failure and determine the uniaxial com- pressive strength and the friction angle of the intact rock.

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If both the major and minor principal stresses for a soil element are known, as well as the strength parameters c'and o': A) Derive the formula that gives the orientation (the angle 0) of the theoretical failure plane. Hint: for the diagram below, assume 0₁ is acting in the vertical direction on the soil element (typical case) - i.e. the orientation of the failure plane with be measured on the Mohr's Circle from the Pole (which will be at 03). Remember a useful property of circles in terms of angles... Øs 03 01 B) Relate your answer from Part A to the failure plane assumed in Rankine's Active Earth Pressure. You can show this relationship with a simple sketch.

The initial effective stresses on a saturated soil element at a certain depth in a soil massare σ1 = 40 kPa, σ2 = 20 kPa, and σ3 = 20 kPa. The groundwater level is well belowthe soil element. The changes in stresses on the soil element are shown in Fig. 1.(a) Calculate the change in principal stresses.(b) Plot the total stress path in (p, q) space, and the effective stress path (assuming that thesoil is a linearly elastic material).(c) The soil is measured with a strength of 30 in shear, if only the vertical load isincreasing, try to predict the maximum of the vertical loading before its failure (withan aid of Mohr-Circle), and to identify the failure direction.

A triaxial test is performed on a cohesionless soil. The soil failed under the following conditions: confining pressure = 250 kPa; deviator stress = 450 kPa. Evaluate the following: a. The angle of shearing resistance of the soil b. The shearing stress at the failure plane c. The normal stress at the failure plane

Q1: A sample was obtained from point A in the submerged clay layer shown below. It was determined that it had: W= 54% G3= 2.78 What is the effective vertical stress at A. h, = 25 m water Saturated clay h, = 15 m A

The angle of friction of a compacted dry sand is 37 degrees. In a direct shear test on the sand, anormal stress of 150 kN/m^2 was applied. The size of the specimen was 50mmx50mx30mm(height) SITUATION 1 a. Compute the shearing stress Your answer       b. What shear force will cause shear failure? Your answer       c. Determine the shear stress at a depth of 3m if the void ratio of the soil is 0.60. Gs Of sand is 2.70

, solve graphically only6. In a consolidated drained triaxial test on an OC clay with a cohesion value of 4 kPa, the total axial stress is17 kPa and the cell pressure is 1 kPaFind:a) The deviator stressb) The angle of the Mohr-Coulomb Envelopec) The angle of the Failure Planed) The values of σff and τffe) The value of τmax