What is Aisc Table J3 2 used for in structural engineering?

Aisc Table J3 2 provides values required for steel design calculations including capacity checks, connection design, and detailing. It is referenced in structural design codes and used by practicing engineers during the design of buildings, bridges, and industrial structures.

Can I use these reference values directly in my design?

Yes, provided the values match your governing code edition and project specifications. Always cross-reference against the primary source (code document, manufacturer data, or published standard). The information on this page is for educational use — final verification by a licensed engineer is required.

How often are these reference values updated?

Reference content is maintained to align with current code editions. When a new edition of AISC 360, AS 4100, EN 1993, or CSA S16 is published, values are reviewed and updated. Check the last-modified date at the bottom of the page and verify against the current edition for your jurisdiction.

Aisc Table J3 2 | Steel Calculator

| Group A | A325, F3125 Gr A | 54 | 68 | | Group B | A490, F3125 Gr B | 68 | 84 | | Group C | F3043 | 79 | 99 |

Threads Included (N) means the shear plane intersects the threaded portion of the bolt shank — the reduced cross-sectional area at the thread root governs. This is the conservative default unless fabrication drawings explicitly position the grip so that the unthreaded shank spans the shear plane.

Threads Excluded (X) means only the full-diameter unthreaded shank is in the shear plane. This requires careful bolt length selection during detailing. The 26% increase in Fnv is substantial enough that many engineers specify Condition X for critical connections.

phi factor (LRFD): phi = 0.75 for all bolt shear checks per AISC 360 Section J3.6.

Design Shear Strength phi*Rn — All Bolt Diameters (Single Shear)

The design shear strength is: phi*Rn = phi × Fnv × Ab, where Ab is the nominal unthreaded body area of the bolt.

Quick Reference — Design Shear phi*Rn (kips) per Bolt

Bolt Dia.	Ab (in.²)	A325-N	A325-X	A490-N	A490-X	F3043-N	F3043-X
1/2	0.196	7.95	10.0	10.0	12.4	11.6	14.6
5/8	0.307	12.4	15.6	15.6	19.3	18.2	22.8
3/4	0.442	17.9	22.5	22.5	27.8	26.2	32.8
7/8	0.601	24.4	30.7	30.7	37.9	35.6	44.6
1	0.785	31.8	40.1	40.1	49.5	46.5	58.2
1-1/8	0.994	40.3	50.7	50.7	62.6	58.9	73.7
1-1/4	1.227	49.7	62.6	62.6	77.3	72.6	91.0
1-3/8	1.485	60.1	75.7	75.7	93.6	87.9	110.2
1-1/2	1.767	71.6	90.1	90.1	111.3	104.6	131.1

Values computed as phi*Rn = 0.75 × Fnv × Ab. Fnv values per AISC 360-22 Table J3.2. Ab values from AISC 360 Table J3.1.

Most Commonly Used Values

Bolt Specification	phi*Rn Single Shear	phi*Rn Double Shear
3/4 in. A325-N	17.9 kips	35.8 kips
3/4 in. A325-X	22.5 kips	45.1 kips
7/8 in. A325-N	24.4 kips	48.7 kips
7/8 in. A325-X	30.7 kips	61.3 kips
1 in. A325-N	31.8 kips	63.6 kips
1 in. A490-N	40.1 kips	80.1 kips

Conversion to ASD

For Allowable Strength Design: Rn/Omega = phi*Rn (LRFD) / 1.5

Bolt Dia.	A325-N ASD	A325-X ASD	A490-N ASD	A490-X ASD
3/4	11.9	15.0	15.0	18.6
7/8	16.2	20.5	20.5	25.3
1	21.2	26.7	26.7	33.0

Thread Condition: N versus X — Design Choice

The thread condition changes per-bolt capacity by roughly 26% for Group A and B bolts.

Condition N — Threads Included in Shear Plane (Default)

Every standard bolted connection starts as Condition N unless detailing explicitly excludes threads from the shear plane. The threaded portion always exists somewhere on the bolt shank, and for standard grip lengths, the shear plane often intersects it.

Condition X — Threads Excluded from Shear Plane

This requires that the fabricator select a bolt length such that the unthreaded shank extends fully through all shear planes. The threaded portion begins only after the last connected ply. Use Condition X when bolt shear governs the connection capacity and reducing bolt count or diameter is critical.

Double Shear — Twice the Capacity

phi*Rn_double = 2 × phi × Fnv × Ab

Common double-shear connections include: beam web to double angles, splice plates with plates on both sides, gusset plates sandwiched between splice plates, and base plate shear keys.

Bolt Group Overview

Group A — A325 / F3125 Gr A (Fnv = 54/68 ksi)

The standard structural bolt. Used in approximately 85% of US building connections. Minimum tensile strength 120 ksi. Type 1 (plain) for indoor use; Type 3 (weathering) for exposed steel.

Group B — A490 / F3125 Gr B (Fnv = 68/84 ksi)

Higher-strength bolt with minimum tensile strength 150 ksi. About 26% stronger than A325 in shear. Not permitted in galvanized connections due to hydrogen embrittlement risk.

Group C — F3043 (Fnv = 79/99 ksi)

Highest-strength group. Minimum tensile strength 200 ksi. Approximately 46% stronger than A325. Application growing in high-seismic and long-span connections.

Worked Example — Bolt Quantity for a Shear Connection

Problem: A W18x35 beam frames into a column with a double-angle shear connection. The factored beam end reaction is Vu = 124 kips. Determine the number of 3/4 in. A325-N bolts required.

Step 1: Determine per-bolt capacity. 3/4 in. A325-N in double shear = 35.8 kips.

Step 2: Calculate required number. n = 124 / 35.8 = 3.47 → use 4 bolts.

Step 3: Alternative with fewer bolts. 3/4 in. A325-X at 45.1 kips each × 3 = 135.3 > 124. OK with 3 bolts.

Bolt Shear vs. Bearing — Which Governs?

Bolt shear strength from Table J3.2 is only one of several limit states. The connection capacity is the minimum of: bolt shear (J3.2), bolt bearing (J3.10), bolt tearout (J3.10), block shear rupture (J4.3), and net section rupture (J4.1). In many practical connections, bearing or block shear governs before bolt shear.

Frequently Asked Questions

What is the shear strength of a 3/4 inch A325 bolt with threads included? Per AISC 360-22 Table J3.2, a 3/4 in. A325 bolt with threads in the shear plane (Condition N) has nominal shear stress Fnv = 54 ksi. Design shear phi*Rn = 40.5 × 0.442 = 17.9 kips per bolt in single shear. In double shear: 35.8 kips.

What is the difference between threads included (N) and threads excluded (X)? Condition N applies when the threaded portion intersects the shear plane; Condition X applies when only the unthreaded shank is in the shear plane. For A325 bolts, Fnv increases from 54 ksi (N) to 68 ksi (X) — a 26% increase. Condition X requires deliberate bolt length selection during detailing.

How do I convert LRFD bolt shear values to ASD? Divide the LRFD phi*Rn by 1.5 to obtain the ASD allowable strength Rn/Omega. For a 3/4 in. A325-N bolt: 17.9 / 1.5 = 11.9 kips.

When should I use A490 bolts instead of A325? Use A490 (Group B) bolts when higher per-bolt shear capacity is required and galvanizing is not part of the corrosion protection system. A490 provides 26% more shear strength than A325.

Does bolt shear capacity double in a double-shear connection? Yes. phiRn_double = 2 × phiFnv × Ab. A 3/4 in. A325-N bolt provides 17.9 kips single shear, 35.8 kips double shear.

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Educational reference only. Verify against AISC 360-22 Table J3.2 and governing project specification.