Bolted Connections Calculator

Single-plate shear tab screening for bolt shear, plate bearing, and block shear. The module uses a rectangular plate, standard holes only, and a bolt-group geometry defined by count, rows, pitch, gage, and edge distances.

Engineering Scope

This page evaluates a bolted shear-tab connection for bolt shear, plate bearing, and block shear using the selected code routine. The governing mode is the lowest capacity reported by the active result set.

The current scope is a single-plate shear tab only. The page is not a slip-critical design tool and does not include direct bolt tension, oversized holes, slotted holes, or prying action.

For AS 4100 workflows, block shear should be treated as an adapted screening output aligned to the current engine implementation. The governing result still requires independent engineer verification because AS 4100 does not provide a standalone clause equivalent to AISC J4.3.

Calculation Model

The module evaluates the following limit states from the entered geometry and load state:

Bolt shear = phi * Fnv * Ab * ns
Bearing = phi * 1.2 * Lc * t * Fu
Block shear = governing code expression for the selected shear-tab geometry

Inputs used in the calculation include bolt diameter, bolt grade, hole type, plate thickness, plate width and length, row count, pitch, gage, edge distances, plate steel properties, factored shear, threads in the shear plane, and the number of shear planes.

Outputs

The page reports bolt shear capacity, bearing capacity, block shear capacity, governing capacity, governing mode, and utilization. The calculation trace exposes the selected code reference and the intermediate values used to form the governing resistance.

Limitations

Connection type is fixed to a single-plate shear tab.
Standard round holes only; oversized and slotted holes are not part of this module.
The page does not implement direct bolt tension, slip-critical pretension, or prying action.
For AS 4100, block shear should be treated as a screening check and verified independently before design use.
All calculations and outputs must be independently verified by a licensed Professional Engineer before design use.

Worked Example

For the default 4 x M20 Grade 8.8 shear tab with a 10 mm plate and 220 kN factored shear, the module evaluates bolt shear, bearing, and block shear independently and reports the lowest capacity as governing. Use the calculation trace to replicate the selected limit state before design use.

Verification

Confirm the code edition, bolt grade, hole type, plate properties, edge distances, and the assumed shear plane condition. For AS 4100, verify block shear separately because the page treats it as an adapted screening output. Then replicate the governing limit state independently by hand or in a spreadsheet.

Disclaimer

All calculations and reported values must be independently verified by a licensed Professional Engineer before use in design, detailing, procurement, fabrication, construction, or permit submission. This tool is provided without warranty of accuracy, completeness, fitness for purpose, or project-specific code compliance. The site operator disclaims liability for any loss, damage, claim, cost, or consequence arising from use of, or reliance on, the calculator or its outputs.