The total cross-sectional area of the cover plating of riveted girders must not exceed _____ of the total flange area.

The total cross-sectional area of the cover plating of riveted girders must not exceed _____ of the total flange area.

• A. 80%
• B. 70%
• C. 90%
• D. 50%

Answer: (C)

When reinforcing riveted girders, adding cover plates increases the flange’s cross-sectional area and stiffness, but there’s a practical upper limit to how much plate area you can use. This keeps the reinforcement from overpowering the original flange and the riveted connections, so the joint behavior assumed in design remains valid. The allowable total cross-sectional area of cover plates is limited to 90% of the flange area, meaning the combined area of all cover plates can be up to 0.9 times the flange area. Going beyond this would overly shift stresses and rivet demands, while this 90% bound provides a safe, workable limit that still lets you enhance strength without destabilizing the joint. Values significantly lower than 90% would be unnecessarily restrictive, so 90% is the established maximum.

When reinforcing riveted girders, adding cover plates increases the flange’s cross-sectional area and stiffness, but there’s a practical upper limit to how much plate area you can use. This keeps the reinforcement from overpowering the original flange and the riveted connections, so the joint behavior assumed in design remains valid. The allowable total cross-sectional area of cover plates is limited to 90% of the flange area, meaning the combined area of all cover plates can be up to 0.9 times the flange area. Going beyond this would overly shift stresses and rivet demands, while this 90% bound provides a safe, workable limit that still lets you enhance strength without destabilizing the joint. Values significantly lower than 90% would be unnecessarily restrictive, so 90% is the established maximum.