> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/templates/truss-bridge-workflow/templates-for-code-check-and-load-rating-tb/gusset-plate-load-rating-tb.md).

# Gusset Plate Load Rating (LFD) \[TB]

The Gusset Plate Load Rating (LFD) template collects the inputs that stay constant across all gusset plate load ratings of the truss — the mapped LFD Load Rating Combination Table and the FHWA-IF-09-014 Part B factors. Each Gusset Plate Load Rating (LFD) object (under the Load Rating section) points at one template to inherit these values so they do not have to be repeated at every plate.

## General

**Load Rating Combination (LFD):** The LFD Load Rating Combination Table used as the basis for the analysis results and load factors of the rating. Pick a Load Rating Combination Table (LFD) that maps the dead load cases and the Design live-load stage. The user must provide a value.

## LFR Factors

**Non Load Path Redundant Penalty on the Rating Capacity:** Factor applied to the rating capacity of every limit state. Use 1.0 for a load path redundant connection and a reduced value (0.9 by default) otherwise.

**Omega, Plate Shear Yielding Reduction \[Stiffness demonstrated = 1.00 / Default = 0.74]:** Reduction applied to the plate shear yielding resistance. Use 1.00 only where adequate plate stiffness is demonstrated; otherwise keep 0.74.

**K, Whitmore Column Effective Length Factor (FHWA Table 2):** Effective length factor K of the Whitmore column in compression. Typical values are 1.2 for an unbraced plate edge that can sway and 0.5 to 0.65 where sway is prevented.

**Fv, Rivet Shear Strength (FHWA Table 1):** Nominal shear strength of the fasteners, in ksi: 18 for rivets driven before 1936 or of unknown origin, 21 after 1936 of unknown grade, 27 for ASTM A502 Grade I and 32 for ASTM A502 Grade II.


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