Engineering Questions with Answers - Multiple Choice Questions

# Mohrs Stress Circle

1 - Question

The shearing resistance of a soil is constituted by ___________
a) Structural resistance and Frictional resistance
b) Shearing strength
c) None of the mentioned
d) All of the mentioned

View Answer

Answer: a
Explanation: The shearing resistance of soil is constituted by
i) The structural resistance to displacement of the soil because of the interlocking of the particles
ii) The frictional resistance to a translocation between the individual soil particles at their contact points.

2 - Question

The shear strength in cohesion less soil is due to ___________
a) Internal friction
b) Cohesion
c) Inter granular friction
d) Inter particle force

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Answer: c
Explanation: The shear strength in cohesion less soils from inter granular friction, while in other soils it results both from internal friction as well as cohesion.

3 - Question

The planes that exist in soil mass is ______________
a) Principal plane
b) Principal stress
c) Stress plane
d) None of the mentioned

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Answer: a
Explanation: In a loaded soil mass, there exist three typical planes, mutually orthogonal to each other. These planes are called the principal planes.

4 - Question

The failure condition for a soil can be expressed in terms of limiting shear stress, called __________
a) Principal stresses and Shear strength
b) Shearing resistances
c) None of the mentioned
d) All of the mentioned

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Answer: a
Explanation: The failure conditions for a soil may be expressed in terms of limiting stress, called shear strength or as a function of the principal stresses.

5 - Question

The shear deformation of soil in a building can cause ___________ of the following?
a) Sinking of footing
b) Slide in an earth embankment
c) Movement of wedge
d) All of the mentioned

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Answer: d
Explanation: Shearing deformation of soil may be in the form of the sinking of a footing, or movement of a wedge of soil particles or on masses upon the action of shear stress.

6 - Question

Major principal stress in a soil is represented by the symbol ________________
a) σ1
b) σ2
c) σ3
d) σ4

View Answer

Answer: a
Explanation: Major, intermediate and minor principal stresses are represented by the corresponding symbols σ1, σ2, and σ3.

7 - Question

The circle obtained from two dimensional stress system is known as ________
a) Principal stress circle
b) Mohr circle
c) Shearing stress circle
d) None of the mentioned

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Answer: b
Explanation: The circle drawn from two dimensional stress systems is known as Mohr’s circle of stress (Mohr, 1870).

8 - Question

The maximum shear stress τmax, for a soil mass is equal to ___________
a) (σ1 – σ3 )/2
b) (σ1 + σ3 )/2
c) (σ1×σ3 )/2
d) (σ3 – σ1 )/2

View Answer

Answer: a
Explanation: The maximum shear stress τmax is equal to (σ1 – σ3)/2 which occurs on planes with α= 45°.

9 - Question

The normal stresses acting on planes of the soil are known as _____________
a) Major principal stresses
b) Principal stresses
c) Minor principal stresses
d) Principal planes

View Answer

Answer: a
Explanation: The normal stresses acting on principal planes are called the principal stresses.

10 - Question

Stress component on planes of a loaded soil mass depends upon ____________
a) Stress acting on plane
b) Direction of plane
c) Shearing resistance
d) All of the mentioned

View Answer

Answer: b
Explanation: Through a point in a loaded soil mass, innumerable planes passes and stress component on each plane depends upon the direction of the plane.