Summary

• Beams are commonly found in many types of structure.
• Beams carry load principally by bending.
• The internal forces generated in beams under load are referred to as bending moments and shear forces.
• The support conditions influence the nature of the bending moments and shear forces.
• The strength of a beam is related to its section modulus.
• The stiffness of a beam is related to its second moment of area.
• Local buckling and shear forces can reduce the bending strength of a beam.
• Lateral torsional buckling is possible in laterally unrestrained beams, in which case the buckling strength is related principally to the slenderness of the beam.