Bolt Combined Tension and Shear (AISC 360 J3.8)
The tension a bracket, hanger, or moment end-plate bolt has left after its shear.
Example
You enter
- Nominal tensile stress Fnt (ksi, 90 A325) 90
- Nominal shear stress Fnv (ksi, 54 N / 68 X) 54
- Nominal bolt area Ab (in²) 0.442
- Required shear stress frv (ksi = V/Ab) 20
- Method LRFD
You get
- Reduced tensile stress F'nt 72.6 ksi
- Avail tension (kip) 24.1
Checked against published worked examples from: AISC.
Details, formula, and sources
ScopeAISC 360-22 J3.8 reduces the nominal tensile stress F'nt = 1.3 Fnt - (Fnt/(phi Fnv)) frv, capped at Fnt. A 3/4 in A325 at 20 ksi required shear drops from 29.8 kip pure tension to 24.1 kip; a fully-sheared bolt floors at zero tension - the reduction a straight tension check misses. Bearing-type interaction (slip-critical is J3.10); shear and bearing are checked separately. A design aid, not the engineer of record's stamped design.
Formula or tablek = (LRFD) Fnt/(0.75 Fnv), (ASD) 2.00 Fnt/Fnv; F'nt = min(1.3 Fnt - k frv, Fnt) (floored at 0); available tension = 0.75 F'nt Ab (LRFD) or F'nt Ab/2.00 (ASD).
Source and editionThe AISC 360-22 Section J3.8 reduced tensile stress for a bearing-type bolt in combined tension and shear, with the Table J3.2 nominal stresses, by name.
Free accessAISC 360 is free to read at aisc.org (Specification for Structural Steel Buildings); the J3.8 provision and Table J3.2 are in the published specification.
What governsEstimate. AHJ and licensed professional govern.
API field namesfnt_ksi, fnv_ksi, ab_in2, frv_ksi, method, fpnt_ksi, avail_tension_kip
- Reduced tension F'nt = 1.3 Fnt - k frv, capped at Fnt (no 1.3 benefit without shear) and floored at zeroAISC 360-22 J3.8
- Nominal stresses Table J3.2: A325 Fnt = 90, Fnv = 54 (threads-N) or 68 (threads-X) ksiAISC 360-22 Table J3.2
- Bearing-type the bearing-type interaction; a slip-critical joint uses the J3.10 slip reductionAISC 360-22 J3.8 / J3.10