Fillet Weld Strength and Size
Throat, ASD/LRFD shear capacity, utilization.
Example
You enter
- Mode capacity-from-size
- Fillet leg size (in) 0.25
- Weld length (in) 6
- Electrode E70
- Method ASD
- Thinner part thickness (in, optional) 0.75
You get
- Throat / unit strength 0.17675
- Stress (ksi) 21
- Capacity (lb) 22270.5
Details, formula, and sources
Throat, ASD/LRFD shear capacity, utilization, and the AISC J2.4/J2.2b min/max fillet size for a steel fillet weld (AWS D1.1 / AISC 360).
Effective throat a = 0.707*leg (equal-leg). ASD allowable shear 0.30*F_Exx; LRFD design 0.75*0.60*F_Exx. Capacity = stress * a * length. AISC min fillet (Table J2.4 by thinner part); max (J2.2b) = t - 1/16 for t >= 1/4. Size-from-load solves the leg for a target load.
Fillet-weld effective throat (0.707*leg) and shear strength (allowable 0.30*F_Exx; LRFD 0.75*0.60*F_Exx) per AWS D1.1 Structural Welding Code - Steel and AISC 360 §J2, by name, with the minimum/maximum fillet sizes of AISC Table J2.4 and §J2.2b.
First-principles weld mechanics. The qualified WPS, the weld inspector, and the engineer of record govern; base-metal and matching-filler checks are the engineer's.
Estimate. AHJ and licensed structural engineer govern.
Field names used by the API: mode, leg_in, length_in, electrode, method, base_thickness_in, throat_in, stress_ksi, capacity_lb
- Electrode strength E60/E70/E80 sets F_Exx; matching filler is the engineer'sAWS D1.1