The symptom of overloads in compression members is which of the following?

• A. Yielding
• B. Cracking
• C. Torsion
• D. Buckling

Answer: (D)

Buckling is the primary sign of overload in a compression member. When a column or member is pushed axially, it can lose stability and bend sideways even before the material yields. This instability, called buckling, shows up as lateral deflection or a curious bent shape along the member. For slender members, the critical load causing buckling can be much lower than the load that would cause yielding, so buckling often governs design and inspection checks. Yielding would mean the material plastically deforms under load, which is different from the abrupt instability of buckling. Cracking implies fracture, and torsion involves twisting—not the typical response to pure axial compression. So the symptom to identify is buckling.