What type of columns are long and fail by buckling, normally assuming an "S" shape?

Slender columns are characterized by their long, thin structure, which makes them susceptible to buckling under load. When subjected to compressive forces, these columns do not yield like stockier columns but instead fail by bending or bending laterally, which creates an "S" shape in their deformation. This behavior occurs because slender columns have a high slenderness ratio, meaning their height is much greater than their width, leading to instability under compressive loads.

In structural engineering, slender columns are carefully designed and analyzed to prevent buckling failures, which can lead to catastrophic structural failures. This contrasts with other types of columns, which may have different load-bearing characteristics and failure modes. For instance, piers are typically more robust and designed for vertical loads, intermediate columns serve a transitional role in supporting beams or girders, and girders themselves are horizontal structural components that support beams or loads, not specifically categorized by buckling behavior. Understanding the unique behavior of slender columns is crucial for fire service personnel to assess risks during firefighting operations and building stability assessments.