Elastic beam analysis · Euler–Bernoulli · units: m · kN · GPa · mm
Governing relations & sign convention
Euler–Bernoulli: EI·v'''' = w(x), V = dM/dx, M = −EI·v''.
x measured from the left end; downward load & downward deflection positive; +M = sagging (tension on the bottom fibre).
Maxima are taken from the analytic curves sampled along the span; combined loading is exact superposition of the point and uniform cases.
Closed-form maxima used as checks
SS point (central) δ = PL³/48EI · SS uniform δ = 5wL⁴/384EI, M = wL²/8 ·
cantilever tip load δ = PL³/3EI · cantilever uniform δ = wL⁴/8EI, M = wL²/2.
Assumptions
Prismatic, linear-elastic, homogeneous member · small deflections · shear deformation neglected · loads in the plane of bending.
Move the cursor across any diagram to read V, M and δ at that section.