Steel Girders – Web Stiffeners (Spacing and Definitions) Which of the following statements regarding web stiffeners in plate girders is correct?

Introduction / Context:
Web stiffeners are provided in plate girders to prevent web buckling under shear and to control panel aspect ratios. They can be vertical (transverse) or horizontal, and their spacing relates to the clear web depth d.

Given Data / Assumptions:

• Plate girder with thin web subjected to shear and bending.
• d denotes clear web depth as defined for the stiffener type considered.
• Design intent: avoid local buckling and ensure panel stability.

Concept / Approach:

Empirical and code-based limits govern stiffener spacing to maintain web panel efficiency. Vertical stiffeners subdivide the web to limit shear buckling length. Horizontal stiffeners raise buckling resistance by reducing clear depth between a horizontal line and the flange.

Step-by-Step Solution:

Verification / Alternative check:

Design handbooks and standard practice confirm these definitions to ensure consistent panel sizing and buckling checks.

Why Other Options Are Wrong:

• Each statement a, b, c is individually correct within its definition domain.
• Therefore the combined correct choice is option d: All the above.

Common Pitfalls:

Mixing the definition of d between vertical and horizontal stiffeners leads to incorrect spacing and ineffective web panelization.

Final Answer:

All the above