ENME251
Mechanics of Solids
Syllabus
- Introduction (2 hours)
- Rigid body and deformable body
- Types of loads on structure
- Concept of elasticity
- Elastic and non-elastic behaviour of solids
- Elastic coefficients and their relations
- Three-Dimensional Stress (6 hours)
- Stress tensor: definition, notation and sign convention
- State of stress at a point
- Stress acting on an arbitrarily oriented plane
- Stress transformation
- Principal stress, principal plane, octahedral stress
- Differential equations of motion of a deformable body
- Von Mises stress
- Analysis of Deformation (6 hours)
- Strain at a point
- Small displacement theory and compatibility relations
- Strain tensor
- Normal and shear strain, plane strain
- Strain acting on arbitrarily oriented plane
- Strain transformation and principal strain
- Volumetric strain
- Strain Energy and Applications of Energy Method (7 hours)
- Definition
- Strain energy density
- Isotropic and anisotropic elasticity
- Strain energy in tension, shear, bending and torsion
- Castigliano's theorem
- Dummy load method
- Curved Beam (4 hours)
- Definition
- Assumptions in stress distribution
- Circumferential, radial, and axial stresses
- Deflection of curved beam
- Statically indeterminate closed ring
- Unsymmetrical Bending and Shear Center (8 hours)
- Definition
- Bending stress due to unsymmetrical bending
- Deflections due to unsymmetrical bending
- Shear flow in thin wall beam cross section
- Shear center for channel section
- Composite beams
- Thin and Thick Wall Cylinder (5 hours)
- Stress and strain in thin cylindrical shell
- Open and closed end thick cylinder
- Circumferential, radial and longitudinal stress
- Linear and volumetric strain
- Composite thick cylinders
- Torsion (5 hours)
- Torsion in triangular, rectangular, and elliptical sections
- Torsion in narrow rectangular cross section
- Torsion of hollow thin wall section
- Contact Stresses (2 hours)
- Point and line contact
- Expressions for principal stresses
Practicals
- Non-linear behaviour of rubber in tension
- Creep test and relaxation test on viscoelastic specimen
- Torsion test of rectangular and triangular section rods; torsion test of circular, square and rectangular closed thin wall tubes
- Deflections and stresses in curved beams
- Stress and strain in thick wall cylinders
- Determination of shear center for a beam with a channel cross section
- Effects of suddenly applied dynamic loads; tension member under dynamic load; sudden transverse loading of a beam
Evaluation
Final exam questions cover all chapters. Approximate marks distribution (total 60 marks over 45 hours):
- Introduction and Contact Stresses: 4 marks
- Three-Dimensional Stress: 8 marks
- Analysis of Deformation: 8 marks
- Strain Energy and Applications of Energy Method: 8 marks
- Curved Beam: 6 marks
- Unsymmetrical Bending and Shear Center: 12 marks
- Thin and Thick Wall Cylinder: 8 marks
- Torsion: 6 marks