The different types of beams can be based on three main categories; Supports, Geometry, and Equilibrium:
- Supports:
- Cantilever Beam
- Fixed Beam
- Overhanging Beam
Based on Supports
Simply Supported Beam
Source: SkyCiv Beam
Simply supported beams are defined as having two supports at either end – one pinned and one roller. This is generally considered as being the most simple type of beam. This is a very common type of beam and is considered determinant – as the beam can be solved using equilibrium equations.
Cantilever Beam
Source: Cantilever Beam Calculator
Cantilever Beams are supported from one end, using a Fixed Support. This is the only type of support that can be used in this scenario as it offers the moment resistance required for the beam to remain static. If a pinned or roller support was used, it would not offer the restraint that the beam would need. A good example of a cantilever beam is a shop awning – where the beam is bolted directly into the wall.
Continuous Beam
Source: SkyCiv Beam
Continuous beams are multi-spanned beams that have multiple supports across the length of the beam. An example of a continuous beam would be a single beam that is supported by a number of columns along its length. This is the only example between the support systems that is considered an indeterminate beam – since there are more unknowns than equilibrium equations available.
Fixed Beam
Source: SkyCiv Beam
Fixed Beams have fixed supports at either end – offering moment resistance at either end. The bending moment within the member will generally have a value at either end of this beam.
Overhanging Beam
Source: SkyCiv Beam
Overhanging beams are those with two supports, but unlike simply supported beams, one of the supports is not at the end of the member. A typical example of this is a balcony which is being extended from a frame structure. The frame offers the two supports, yet no support exists at the end of the member – allowing it to ‘overhang’ as the name suggests.
