Beam Analysis

What you can analyze

Beam Analysis is pure structural analysis: no design code, no material, just stiffness, supports and loads. Use it for any beam where you need moment, shear, deflection and reactions before you pick a member. Every input and output is described in the Beam Analysis documentation, and signs follow the analysis sign and axis conventions.

• Any span layout. Simple spans, cantilevers, propped cantilevers and multi-span continuous beams, with unlimited supports and loads.
• Any material. Enter bending stiffness EI and axial stiffness EA, or link them from a cross-section calculator.
• Reactions that link onward. Support reactions link as point loads into another Beam Analysis, or into a Portal Frame or Truss Analysis wizard. See how linked calculations update.

Need reactions in a column or footing?

Beam Analysis reactions do not link into column or footing calculators. To carry beam reactions down the load path, use Beam Analysis with Load Cases or with Load Combinations (ASD or LRFD). Their reactions link into column and footing calculations.

Just need a quick check?

For a one-off moment, shear and deflection check with no project, use the free beam calculator. It needs no sign-up.

How it calculates

The beam is solved with a finite element beam solver. You give it the beam length, stiffness, supports and loads, and it returns internal forces, deflections and reactions along the beam.

Analysis model

The solver uses the bending stiffness EI and axial stiffness EA you enter for the section. Both can be typed in, or linked from a cross-section calculator that has been set to analyze its section.

A single unfactored load case is used: every load is applied at its entered magnitude. For factored load cases or combinations, use Beam Analysis with Load Cases, or Beam Analysis with Load Combinations (ASD or LRFD).

Supports and loads

• Supports: fixed, pinned, roller or hinge, at any position. An end with no support is treated as a cantilever.
• Springs: axial or lateral linear springs, and rotational springs, each with a stiffness you enter. A spring cannot restrain the same direction as a rigid support at that point.
• Continuous supports: pinned or roller rigid supports, or axial or lateral spring supports, between a start and end position. These are modeled as a series of closely spaced supports.
• Loads: distributed loads (uniform or linearly varying), point loads, axial loads and moment loads, at any position along the beam.

Beams can be horizontal or inclined at an angle you set. On an inclined beam, loads can act along the global axes or aligned with the beam.

Reported results

The governing outputs are the extremes across the whole beam:

• M* - the maximum of the positive and negative bending moments
• V* - the maximum shear
• δ - the maximum deflection, positive downward
• N* and extension - shown when axial loads act, with compression and shortening positive
• R*, Rx*, Rm* - the maximum lateral, axial and moment reactions

Per-span tables report positive, Q1, midpoint, Q3 and negative moments, and the deflection of each span. A support table lists the position, reaction, moment and shear at each support. Shear, moment, deflection and free body diagrams are drawn along the beam.