What is the minimum size of the anchor bolt that can be used in seismic category D or less?

What is the minimum size of the anchor bolt that can be used in seismic category D or less?

• A. 1/4 inch
• B. 3/8 inch
• C. 1/2 inch
• D. 5/8 inch

Answer: (C)

Anchor bolts must be sized to carry the expected seismic forces, and the required minimum diameter increases with seismic risk. For seismic category D or less, the standard minimum is 1/2 inch. This size provides enough withdrawal and shear capacity for typical connections without being unnecessarily large. A smaller bolt, like 1/4 inch or 3/8 inch, wouldn’t meet the required strength for seismic loads in category D or less. A larger bolt, such as 5/8 inch, is specified for higher seismic categories where greater strength is needed.

Anchor bolts must be sized to carry the expected seismic forces, and the required minimum diameter increases with seismic risk. For seismic category D or less, the standard minimum is 1/2 inch. This size provides enough withdrawal and shear capacity for typical connections without being unnecessarily large. A smaller bolt, like 1/4 inch or 3/8 inch, wouldn’t meet the required strength for seismic loads in category D or less. A larger bolt, such as 5/8 inch, is specified for higher seismic categories where greater strength is needed.