An I-section is a beam or bar with an I- or H-shaped cross-section: two flanges connected by a web. This shape is highly efficient in bending, because the material in the flanges lies far from the neutral axis; as a result the section modulus is large at a relatively low weight.
Characteristics
- Two flanges connected by a web
- Large section modulus at a relatively low weight
- In steel there are well-known standardized series such as IPE, HEA, HEB and INP
- Besides steel, I-sections also occur in aluminium and in wood (the wooden I-joist)
Application
- Beams
- Columns
- Load-bearing structures
Rule of thumb: H-sections (HEA/HEB) have wide flanges and are suitable as columns, while IPE sections are narrower and taller and are often used as beams.
Related terms
- Wooden I-joist
- IPE beam
- HEA beam
- Beam
- Structural steel
- Flange
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