Weld Design (AISC/AWS)

structural

Designs and checks welded connections per AISC 360 and AWS D1.1. Calculates fillet and groove weld capacity, effective throat area, demand/capacity ratio, and enforces minimum/maximum weld size rules.

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Weld Type

Weld joint type. Fillet welds are most common for lap and tee joints; groove welds (CJP/PJP) are used for butt joints per AWS D1.1. If omitted, defaults to 'fillet'.

Weld Length In*

Total effective length of the weld line in inches. Per AISC J2.2b, minimum effective length is 4 times the weld leg size. Effective weld length. Minimum: 4 × weld size per AISC J2.2b. Typical: 4-36 in.

Weld Size In*

For fillet welds: leg size in inches (e.g., 0.25 for 1/4" fillet). For groove welds: effective throat depth. Must satisfy AISC Table J2.4 minimum and J2.2b maximum size limits. Fillet weld leg size. Common: 3/16, 1/4, 5/16, 3/8 in. See AISC Table J2.4 for min.

Electrode Classification

AWS electrode classification (e.g., E70xx, E80xx). The numeric portion indicates the electrode tensile strength in ksi. E70xx is standard for A36/A992 steel. If omitted, defaults to 'E70xx'.

Welding Process

Welding process designation per AWS (SMAW, GMAW, FCAW, SAW). Affects electrode properties and deposition rates. If omitted, defaults to 'SMAW'.

Applied Axial Kips

Factored axial force demand on the weld group in kips (LRFD). Positive = tension, negative = compression. Axial force on the weld group. Typical: 10-200 kips for beam connections. If omitted, defaults to 0.0 (no axial load).

Applied Shear Kips

Factored shear force demand on the weld group in kips (LRFD). Combined with axial via vector sum for total demand. Shear force on the weld group. Typical: 10-150 kips for beam end connections. If omitted, defaults to 0.0 (no shear load).

Applied Moment Kip In

Factored moment demand on the weld group in kip-in (LRFD). Converted to equivalent force using moment_arm_in or weld_length_in. Applied moment on weld group. Typical: 50-2000 kip-in for moment connections. If omitted, defaults to 0.0 (no moment).

Base Metal Thickness In

Thickness of the thinner part being joined, in inches. Governs minimum fillet weld size per AISC Table J2.4 and maximum size per J2.2b. If omitted, defaults to 0.5 in.

Base Metal Fu Ksi

Ultimate tensile strength of the base metal in ksi. Used for base metal shear rupture check. Typical: 58 ksi (A36), 65 ksi (A992/A572-50). If omitted, defaults to 65.0 ksi (A992).

Num Welds

Number of identical weld lines in the connection. For a double-sided fillet weld, use 2. Multiplies effective area proportionally. Number of weld lines resisting the load. Typical: 2 for double-sided fillet welds. If omitted, defaults to 1.

Moment Arm In

Distance from the weld group centroid to the line of action for moment-to-force conversion, in inches. If omitted, weld_length_in is used conservatively.

Reference data

This calculator pulls live values from the following engineering reference tables in the database.

weld specifications
steel shapes

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Weld Design (AISC/AWS) is part of the Engineering Database calculator suite. Each tool runs deterministic calculations against authoritative reference data and code-compliant methods, so results are reproducible and traceable to source standards.

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