Pick bolt count and diameter, set the demand — the connection detail and capacity bar update live.
Members don't float in space — they connect. A bolted shear connection transfers beam reactions through bolts in shear. Each bolt has a shear capacity (φRn per bolt). Total connection capacity = number of bolts × capacity per bolt. The beam web and plate also need checks (bearing, tearout, block shear), but bolt shear usually governs for simple connections. Values shown use A325-N bolts in single shear with φ = 0.75.
A perfectly designed beam connected to a perfectly designed column means nothing if the connection between them fails. Connections must transfer the forces that the members are designed to carry — shear, moment, or both. A shear connection (the most common type) transfers only the vertical reaction from the beam to the support. The connection's capacity must equal or exceed the beam's end reaction.
In a bolted shear connection, bolts transfer force through shear across their cross-section. Each bolt has a capacity based on its diameter, grade, and number of shear planes. For A325-N bolts in single shear: the capacity is φRn = φ × Fnv × Ab where Fnv is the nominal shear stress (54 ksi) and Ab is the bolt area. Total connection capacity = number of bolts × capacity per bolt. The tool below lets you size a simple bolted connection.