This document discusses compression members, which are structural elements that experience compressive forces. It defines various terms for compression members like struts, columns, stanchions, and posts. Common cross section shapes used for compression members are listed, along with the main failure modes of crushing and buckling. Key design considerations for compression members mentioned are effective length, slenderness ratio, and selecting an economical cross section.

1. COMPRESSION MEMBERS AS STRUT
• Column, top chords of trusses, diagonals and
bracing members are all examples of compression
members
Truss

2. VARIOUS TERMS USED FOR
COMPRESSION MEMBER
• Strut : it is compression member of truss
• Column: it is compression member of buildings
• Stanchion: it is a built-up column with heavy
loads.
• Post: this term indicate compression member of
wooden structure.
• Boom: compression member of crane

3. • Common section used as Compression members
member
Single & Double Angles
Channel I-Section
(Joist / Beam)
Rod
Composite section
Tube Section
Hollow Section

4. • Modes of failure of Compression member
Crushing failure Buckling failure

5. Terms used in design of compression member
• Effective length (KL)
• Slenderness Ratio (𝜆𝑒𝑓𝑓)
• Economical Cross section

6. • Effective length of Column (KL):
• The effective length, KL, is calculated from the actual length (L) of the member,
considering the rotational and relative translational boundary conditions at the ends
Discontin
uous
angles
Discontin
uous
angles

7. • Maximum slenderness ratio (Stiffness Requirement)

8. Economical Cross section

10. • Where

11. Buckling class of cross sections