Steel Beam Bearing Plate Calculator (AISC 360) - LRFD & ASD
Free AISC 360 steel beam bearing plate calculator. Check all 3 limit states and get minimum bearing plate dimensions instantly.
Quickly design and verify steel beam bearing plates with this free AISC 360-16/22 compliant calculator. It simultaneously checks all three governing limit states — concrete/masonry bearing (J8), web local yielding (J10.2), and web crippling (J10.3) — for both LRFD and ASD methods.
Enter your beam section, reaction, and plate dimensions to receive real-time pass/fail verdicts, demand-to-capacity ratios, required dimensions, and step-by-step calculations. Use the Auto-Solve feature to instantly determine the minimum compliant plate size.
Accurate, code-compliant, and engineer-friendly — perfect for structural steel design. Always verify with a licensed Professional Engineer for construction use.
SteelSolver.com
🔧 Steel Beam Bearing Plate Calculator
AISC 360 code-compliant design & verification — checks all 3 governing limit states simultaneously with real-time pass/fail output.
AISC 360-16/22
LRFD & ASD
J8 • J10.2 • J10.3
Free Tool
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How to use: Fill in beam properties, reaction load, and support details. Hit Calculate to get all three AISC limit-state checks instantly. Use Auto-Solve to find the minimum compliant plate size automatically.
Unit System
📏 Section A — Beam Properties
Select a standard AISC section to auto-fill d, t𝑤, tⁱ, k, k1 — or choose Manual Entry to type your own.
Nominal depth of beam section
Web plate thickness
Tabulated k value from AISC manual
k1 from AISC table (for plate cantilever n)
⚡ Section B — Reaction & Load
Total factored reaction at support
⚠️ End vs. interior changes J10 formulas. Wrong selection = unconservative design.
Used to classify end vs. interior condition (a > d = interior)
🏗️ Section C — Support / Bearing Surface
Limits maximum bearing length N
📐 Section D — Bearing Plate Geometry
Parallel to beam flange. Typically ≥ flange width for full contact.
Along beam span direction. This is the key variable for web checks.
Leave as 0 to auto-calculate minimum required thickness.
⚠️ Results are based on AISC 360-16/22 equations. Always verify with a licensed Professional Engineer before use in construction documents. Not a substitute for project-specific engineering judgment.
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Fill in the inputs and click Calculate to see results here. Or switch back to the Inputs tab.
𝑓 Formulas & Code References (AISC 360)
Limit State 1 — Concrete/Masonry Bearing Strength (AISC J8)
Allowable Bearing Stress
LRFD allowable bearing pressure on concrete:
\[F_p = 0.85 \, f'_c \sqrt{\frac{A_2}{A_1}} \leq 1.7 \, f'_c\]
Required plate area:
\[A_{req} = \frac{R_u}{\phi_c \, F_p} \quad \text{(LRFD, } \phi_c = 0.65\text{)}\]
\[A_{req} = \frac{R \cdot \Omega_c}{F_p} \quad \text{(ASD, } \Omega_c = 2.31\text{)}\]
A1 = plate contact area; A2 = full bearing area of support. Ratio capped at 2.0.
Limit State 2 — Web Local Yielding (AISC J10.2)
At Beam END (distance from end ≤ d)
\[\phi R_n = \phi \, F_{yw} \, t_w (2.5k + N) \quad \phi = 1.00\]
\[\frac{R_n}{\Omega} = \frac{F_{yw} \, t_w (2.5k + N)}{1.50}\]
At INTERIOR Location (distance from end > d)
\[\phi R_n = \phi \, F_{yw} \, t_w (5k + N) \quad \phi = 1.00\]
Solving for minimum N (at end):
\[N_{min} = \frac{R_u}{\phi \, F_{yw} \, t_w} - 2.5k\]
k = fillet distance from AISC table (not k-design). Fyw = yield stress of web.
Limit State 3 — Web Crippling (AISC J10.3)
At Beam END, when a/d < 0.2
\[\phi R_n = \phi \cdot 0.40 \, t_w^2 \left[1 + 3 \left(\frac{N}{d}\right)\left(\frac{t_w}{t_f}\right)^{1.5}\right] \sqrt{\frac{E \, F_{yw} \, t_f}{t_w}}\]
At INTERIOR Location, a/d ≥ 0.2
\[\phi R_n = \phi \cdot 0.80 \, t_w^2 \left[1 + 4 \left(\frac{N}{d}\right)\left(\frac{t_w}{t_f}\right)^{1.5}\right] \sqrt{\frac{E \, F_{yw} \, t_f}{t_w}}\]
φ = 0.75 (LRFD) | Ω = 2.00 (ASD)
E = 29,000 ksi (steel modulus of elasticity). a = distance from beam end to nearest load.
Plate Thickness Design — Cantilever Bending
Cantilever projection n of plate beyond beam flange:
\[n = \frac{B - 2 k_1}{2}\]
Bearing pressure under plate:
\[f_p = \frac{R}{B \times N}\]
Required plate thickness from bending of cantilever:
\[t_{req} = \sqrt{\frac{3 \, f_p \, n^2}{F_y}}\]
Fy = plate yield strength. n = cantilever overhang beyond flange/k1. fp = actual bearing pressure.
📋 Variable Definitions
| Symbol | Description | Units (Imperial) |
|---|---|---|
| R / Ru | Beam reaction (ASD / LRFD factored) | kips |
| d | Overall beam depth | in |
| tw | Web thickness | in |
| tf | Flange thickness | in |
| k | Distance from outer face of flange to web toe of fillet | in |
| k1 | Distance from web centerline to flange edge (for n calc) | in |
| N | Bearing length (along beam span) | in |
| B | Plate width (perpendicular to span) | in |
| t | Plate thickness | in |
| n | Cantilever projection of plate beyond k1 | in |
| Fyw | Yield stress of web steel | ksi |
| Fy | Yield stress of plate steel | ksi |
| f'c | Concrete compressive strength | psi |
| Fp | Allowable bearing pressure on support | ksi |
| fp | Actual bearing pressure (R / B×N) | ksi |
| E | Modulus of elasticity of steel = 29,000 ksi | ksi |
| A1 | Plate contact (bearing) area = B × N | in² |
| A2 | Full bearing area of support | in² |
| DCR | Demand-to-Capacity Ratio (demand / capacity) | — |
| a | Distance from beam end to point of load application | in |
📐 Bearing Plate Schematic — Labeled Dimensions
Steel Beam End on Bearing Plate — Section View
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The diagram is a schematic representation. N is the critical dimension along the beam span. The web checks (J10.2 & J10.3) both depend on N, making it the primary design variable. B must be ≥ beam flange width for full bearing, and governs the cantilever projection n for plate thickness.