How to Use the Bolt Count for Shear Connection Calculator
When designing a bolted steel connection that resists shear, you divide the total shear load by the design shear strength of one bolt to find the minimum number of bolts needed. This calculator applies the AISC Specification (AISC 360, Section J3.6) method for bearing-type bolted connections.
The nominal shear strength per bolt equals the bolt's shear area times its nominal shear stress (Fnv), using the standard AISC values of 54 ksi for A325 bolts and 68 ksi for A490 bolts with threads included in the shear plane (the conservative case). A resistance factor of 0.75 is applied to get the design shear strength, and double shear connections double the capacity per bolt.
This calculator gives a simplified reference value based on shear strength alone. A complete design also needs to check bolt spacing, edge distance, and plate bearing and tearout strength, so confirm the final connection design with a licensed structural engineer.
Frequently Asked Questions
The total shear load is divided by the design shear strength of one bolt (shear area x shear stress x resistance factor), then rounded up to the nearest whole bolt.
Yes. This calculator uses the conservative threads-included (N) shear values from AISC. If threads can be excluded from the shear plane, actual capacity is higher.
No. This is a simplified shear-strength-only reference value. Bolt spacing, edge distance, and plate bearing strength must be checked separately, so confirm the final design with a licensed structural engineer.