Name of the College : Mahatma Gandhi University
Department : Civil Engineering
Subject Code/Name : MCEGS 102/THEORETICAL GEOMECHANICS
Sem : I
Website : mgu.ac.in
Document Type : Model Question Paper
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/mgu.ac.in/5003-MCEGS%20102%20Theoretical%20Geomechanics%20-1.pdf
Theoretical Geomechanics Question Paper :
M.TECH. DEGREE EXAMINATION :
Model Question Paper – I
Branch: Civil Engineering
Related : MGU MCEEE106-4 Environmental Impact Assessment M.Tech Model Question Paper : www.pdfquestion.in/5002.html
Specialization: Geomechanics and Structures
First Semester :
MCEGS 102 : THEORETICAL GEOMECHANICS
(Regular – 2013Admissions)
Time : 3 Hours
Maximum: 100 Marks
1.a) The stress components at a point are x=50, y=30, z=15, xy=20, yz=5, xz=10 MPa. If the co-ordinate system is rotated about Z axis in anti clockwise direction through 300. Prove that the stress invariants remains unchanged (15)
b) State and explain Mohr circle of stresses. (10)
OR
2. a) Define octahedral stresses, spherical stresses, deviator stresses and plane stresses as applied
to soil mass. (12)
b) At a point in body the components of strain tensor Determine the principal strain and their orientation with respect to x,y,z co-ordinate axis. (8)
c) The normal stresses on a plane are 1=9, 2=6, 3=3KPa.Determine the normal and shearing stresses on a plane whose direction cosines are 1 (5)
3. (a) A rectangular foundation 2m x 3m transmits a pressure of 360 kN/m2 to the underlying soil. Determine vertical stress at a point 1m vertically below a point lying outside the loaded area, 1m away from a short edge and 0.5m away from a long edge. Use Boussinesq’s theory (15)
(b) Obtain an expression for vertical stress for a uniform load on circular area (10)
OR
4. (a) The load from a continuous footing of 1.8m width, which may be considered to be strip load of considerable length, is 180 kN/m2.
Determine the maximum principal stress at 1.2m depth below the footing, if the point lies
i. Directly below the centre of the footing
ii. Directly below the edge of the footing
iii. 0.6m away from the edge of the footing
What is the maximum shear stress at each of these points? What is the absolute maximum shear stress and at what depth will it occur directly below the middle of the footing? (15)
(b) A raft of size 4m x 4m carries a uniform load of 200kN/m2. Using the point load approximation with four equivalent point loads, Calculate the stress increment at a point in the soil which is 4m below the centre of the loaded area. (10)
5 (a) With the aid of a mechanical model simulate and explain load deformation behavior of material (13)
(b) Briefly explain the pore pressures developed in soil by applied stresses (12)
OR
6. (a) Explain the rheological property of material (10)
(b) Define permanent set with respect to deformation aspect of a material subjected to loading and un loading. (15)
7. (a) Mention the influence of intermediate principal stress on failure (13)
(b) Discuss the frictional aspect of various soils with packing and how failure theory can be applied to cohesionless soils (12)
OR
8. Write short note on (25)
i. Viscous models
ii. Hvorselev’s parameter
iii. Isotropic elastic soil model
iv. Tresca failure theory
v. Mohr-Coulomb failure theory
M.Tech. Degree Examination :
Model Question Paper – II :
Branch : Civil Engineering
Specialization : Geomechanics and Structures
First Semester
MCEGS 102 Theoretical Geomechanics : (Regular – 2013Admissions)
Time : 3 Hours
Maximum : 100 Marks
1. a) Derive Strain compatibility equation. (8)
b) The stress components at a point are σx=50, σy=30, σz=15, τxy=20, τyz=5, τxz=10 MPa. If the co-ordinate system is rotated about Z axis in anti clockwise direction through 300. Determine new stresses (10)
c) The normal stresses on a plane are σ1=10, σ2= -6, σ3=3KPa.Determine the normal and shearing stresses on a plane whose direction cosines are , , . (7)
OR
2. a) Differentiate plane stress and plane strain problems (8)
b) At a point in body the components of strain tensor are Єx=0.01, Єy=-0.005, Єz=0.005, γxy=0.03, γyz=0.01, γxz=-0.08. Determine the principal strain and principal strain direction. (9)
c) Define Deviator stresses (8)
3. (a) A rectangular foundation 2m x 4m transmits a pressure of 450 kN/m2 to the underlying soil. Determine vertical stress at a point 1m vertically below a point lying within the loaded area, 1m away from a short edge and 0.5m away from a long edge. Use Boussinesq’s theory (15)
(b) Obtain an expression for vertical stress for a uniform load on circular area (10)
OR
4. (a) A raft of size 4m square carries a load of 200 kN/m2. Determine the vertical stress increment at a point 4m below the centre of loaded area using Boussinesq’s theory. Compare the result with that obtained by equivalent point load method and with that obtained by dividing the area into 4 equal parts. The load from each of which is assumed to act through centre. (10)
(b) For a strip load of intensity q kN/m2, obtain expression for
i. Normal stress
ii. Tangential stress
iii. Principal stress (15)
5 (a) Write short note on settlement computation (13)
(b) Define permanent set with respect to deformation aspect of a material subjected to loading and un loading. (12)
OR
6. (a) Explain rheological equation of state (10)
(b) With the aid of a mechanical model simulate and explain load deformation behavior of material (15)