Which feature is NOT typically used to transfer lateral shear in long-span bridges?

• A. Diaphragms
• B. Cross-frames
• C. Vertical stiffeners
• D. Aesthetic lighting

Answer: (D)

In long-span bridges, transferring lateral shear effectively requires components that create a transverse and vertical load path, tying the deck and girders together so shear can flow toward supports. Diaphragms provide transverse bracing between girders, enabling shear to be carried across the deck. Cross-frames connect adjacent members and form a lattice that distributes shear and stabilizes the structure under lateral loads. Vertical stiffeners increase local and global rigidity, preventing buckling and helping carry shear along the web and through the connected elements. Aesthetic lighting, by contrast, is a non-structural feature added for appearance or illumination and does not participate in the structural load path, so it does not transfer lateral shear.