Strength of Materials

Strength of Materials for GATE Mechanical and Civil Engineering, one topic per lesson: the theory in plain words, the formulas, a solved example, and GATE-style questions (MCQ, MSQ and NAT) whose numerical answers are recomputed by a program when the site is built.

Start the first lesson

1Stress and Strain

  1. Stress, Strain and Elastic ConstantsNormal and shear stress, strain, Hooke's law, the stress-strain curve, elastic constants E, G, K and Poisson's ratio, bars of varying section, composite bars and thermal stress.
  2. Mohr's Circle, Principal Stress, Thin CylindersStress transformation, principal stresses and planes, maximum shear stress, Mohr's circle, strain gauges, and hoop and longitudinal stresses in thin cylinders and spheres.

2Beams

  1. Shear Force and Bending Moment DiagramsSign conventions, shear force and bending moment diagrams for cantilevers and simply supported beams under point loads, UDL and moments, the load-shear-moment relations and points of contraflexure.
  2. Bending and Shear Stresses in BeamsThe flexure formula M/I = σ/y = E/R, section modulus, beams of uniform strength, shear stress distribution in rectangular and circular sections, and the shear centre.
  3. Deflection of BeamsThe elastic curve EI y'' = M, double integration, Macaulay's method, moment-area theorems, and standard slope and deflection results for cantilevers and simply supported beams.

3Torsion and Columns

  1. Torsion of Shafts and SpringsThe torsion equation T/J = τ/r = Gθ/L, solid and hollow shafts, power transmission, combined bending and torsion, and close-coiled helical springs in series and parallel.
  2. Columns, Strain Energy and Theories of FailureEuler buckling load and effective lengths, slenderness ratio and Rankine's formula, strain energy, impact loading, Castigliano's theorem, and the theories of failure.