Course105106172104 lectures
Mechanics of Materials
Prof. Saravanan.U · IIT Madras
About
This first course in mechanics of deformable bodies introduces the four concepts - Force, stress, strain, displacement - and the four equations that connect them, namely equilibrium equations, constitutive relation, compatibility condition and strain displacement relation.Systematic procedure to solve problems of engineering interest is outlined. In particular, force and displacement relation of structural elements subjected to uniaxial stress, bending, twisting and inflation is studied. Estimation of possible modes of failure of these structural elements and the failure load is outlined.
INTENDED AUDIENCE : Any Interested learners
PREREQUISITES : Engineering Mechanics, Basic Calculus
Lectures
Week 1 : Introduction and Mathematical Preliminaries
- Introduction to the course - Why this course?
- Introduction to the course - Concepts and equations in this course
- Introduction to the course - Objectives and prerequisite
- Mathematical Preliminaries - Linear Algebra
- Mathematical Preliminaries - Vector Algebra
- Representation of Vector
- Tutorial 1
Week 2 : Concept of Force, Displacement and stress
- Concept of Force
- Definition of a body
- Motion and Displacement field
- Traction
- Properties of traction
- Defnition of stress tensor and linear function
- Tensor Algebra
- Meaning of components of the stress tensor
- Tutorial 2
Week 3 : Transformation of stress and equilibrium equation
- Transformation of stress components
- Mohr's Circle derivation
- Example 1: Construction of Mohr's circle
- Example 2: Extremum normal and shear stress
- Example 3: Transformation of stress components
- Uniaxial stress
- Hydrostatic, pure shear and deviatoric stress
- Biaxial and Plane state of stress
- Extreme stress for 3D stresses
- Extremum shear stress
- Stresses in the Octahedral plane
- Tutorial 3
Week 4 : Concept of strain
- Stretch ratio and strain
- Curves and arc Length
- Gradient
- Deformation and displacement Gradient
- Right Cauchy Green Deformation tensor
- Homogeneous deformation
- Engineering strain
- Change in Angle
- Transformation of strain components/ Strain Rosette
Week 5: Governing equations in mechanics
- 2D Equilibrium equations
- 3D Equilibrium equations
- Compatibility condition
- Constitutive relation
- Young's Modulus and Poisson's Ratio
- Shear Modulus
- Bulk Modulus
- Restriction on material parameters
- Strain energy, load potential and total potential
Week 6 : Displacement due to uniaxial loading, temperature and bending
- Thermal strain
- Stepped shaft subjected to axial force
- Inhomogeneous bar subjected to axial force
- Stepped shaft subjected to raise in temperature
- Traction in member subjected to bending
- Governing equilibrium equations
- Displacement field
- Bending equation
- Radius of curvature
Week 7 : Stresses and deflection in homogeneous beams loaded about one principal axis
- Shear force and bending moment diagram
- Variation of axial stress
- Deflected shape and rotation of cross section
- Expression to find shear stress
- Finding centroid of a cross section
- Parallel axis theorem and its application
- Vertical shear stress in I section
- Horizontal shear stress in I section
- Connection design
Week 8 : Stresses and deflection in beams loaded about one principal axis
- Definition of shear center
- Shear center of Channel section
- Expression to find shear center
- Shear force and bending moment diagram
- Finding allowable load
- Modified bending equation
- Bending of a composite beam
- Connection design
week 9 : Stresses and deflection in beams not loaded about principal axis
- Moment of Intertia about arbitrarily oriented axis
- Example: Angle section
- Bending equation for bending about principal axis
- Bending equation about arbitrary axis
- Neutral axis
- Load not about principal axis
- Load about principal axis
Week 10 : Stresses and displacement due to torsion or inflation
- Displacement field
- Torsion equation
- Example problems: Closed sections
- Twisting of open sections
- Example problems: Open sections
- Twisting of thin walled closed sections
- Example problems: Thin walled sections
- Cylindrical polar coordinate system
Week 11 : Pressure vessels and Failure criteria
- Displacement field
- Governing differential equation and solution
- Example problems : Thick walled cylindrical vessel
- Thin walled pressure vessels
- General concepts in failure criteria
- Different failure modes
- Tresca Condition
- vonMises condition
- Maximum normal stress or rankine condition
- Mohr - Columb condition
- Drucker-Prager Condition
- Numerical Example: Pressure vessel and failure theory
Week 12 : Buckling
Syllabus and materials
At NPTEL, as the course publishes them.
Credits and licence
- Institution
- IIT Madras
- Department
- Civil Engineering
- Teacher
- Prof. Saravanan.U
- Level
- Undergraduate
- Language
- English
- Subjects
- Engineering
- Source
- NPTEL
- Licence
- CC BY-NC-SA, as NPTEL states it. Non-commercial use only. NPTEL's terms
- Attribution
- NPTEL states: "Distributed under Creative Commons Attribution-ShareAlike / CC BY - NC - SA", beside a BY-NC-SA badge.
- Who can watch
- NPTEL gives no rating. Invisible Network shows it to Tweens profiles and older, judged from what the source says about it. How courses are placed