Concentric circular pattern only
Eccentric bolt-group shear
Inputs
Integer count of identical joints arranged at one common radius.
Centroid-to-bolt center radius for the concentric circular pattern.
Positive magnitude of one in-plane shear load.
Perpendicular offset between the force line and the bolt-pattern centroid.
Nominal unthreaded shank diameter used only for nominal shear stress output.
Results
Applied eccentric moment
800
Direct shear per equal joint
2,000
Torsional shear magnitude per jointτt
2,000
Conservative scalar joint shear
4,000
Nominal maximum shank shear stress
50.93
M = Fe; Vdirect = F/n; Σr² = nr²; Vtorsion = Mr/Σr² = M/(nr); Vconservative = Vdirect + Vtorsion; τnom = Vconservative/(πd²/4)
A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.
Nearby: Axial response · Beam deflection & reactions · Elastic stability · Solid-shaft torsion
Method
Formula, when it applies, and when it does not
Calculate direct shear per joint, torsional shear magnitude, and a conservative scalar maximum for one in-plane eccentric shear load on an equal-bolt circular pattern.
M = Fe; Vdirect = F/n; Σr² = nr²; Vtorsion = Mr/Σr² = M/(nr); Vconservative = Vdirect + Vtorsion; τnom = Vconservative/(πd²/4)
When
- Equal bolts
- Concentric circular pattern
- In-plane shear only
- Scalar conservative superposition
Don’t
- This is an equal-bolt, concentric circular-pattern, in-plane eccentric-shear screen. The displayed maximum is a conservative scalar sum of direct and torsional shear magnitudes rather than a resolved individual-bolt vector. It does not model arbitrary coordinates, unequal fastener stiffness, preload, friction/slip, axial tension, prying, out-of-plane loads, plate flexibility, interactions, fatigue, material allowables, failure, selection, or approval.
Shigley's Mechanical Engineering Design — eccentrically loaded bolt groups