Truss Analysis Calculator | StructuralClaw

What it checks

The module performs planar (2D) truss analysis using the direct stiffness method. It treats members as two-force axial elements, where each node possesses two degrees of freedom: horizontal and vertical displacement. The engine calculates member axial forces, joint deflections, and support reactions based on the provided geometry and loading. The design method is material-agnostic and does not perform code-based strength checks. Instead, it computes stress as force divided by area and provides a placeholder utilization ratio. The sequence of checks implies a linear elastic response, solving the global stiffness matrix to determine displacements, which are then used to derive internal forces and reactions.

Inputs

Geometry - Node coordinates and member connectivity, with lengths in feet.
Material Properties - Modulus of elasticity (E) in ksi.
Section Properties - Cross-sectional areas in in^2.
Loading - Applied loads in kips.
Node Identification - Node IDs, which may be non-contiguous.

What it reports

Axial Force - Member force in kips, where positive values indicate tension and negative values indicate compression.
Stress - Calculated as force divided by area, reported in ksi.
Utilization - A placeholder ratio calculated as absolute stress divided by (0.6 * E_ksi * 0.001).
Reactions - Support reactions at each node, listed as node ID, horizontal reaction (rx_kips), and vertical reaction (ry_kips).
Overall Status - A boolean flag indicating whether all absolute stresses are less than 0.5 * E.
Displacements - Joint deflections derived from the solution of the stiffness matrix.

Code references

The engine cites "Direct-stiffness planar truss — material-agnostic (no code check)". It does not reference specific structural design codes for member capacity, as material checks are intended to be performed by separate member modules.

Limits

The module is limited to planar (2D) analysis and does not handle three-dimensional structures. It is material-agnostic and does not perform code-based strength checks; the utilization and overall status fields are placeholders that require yield strength (Fy) input for real use. The module assumes linear elastic behavior and does not account for geometric nonlinearity or plasticity. Results are engineering aids; the engineer of record is responsible for the design.

This module ships in the desktop app

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