Practical Axial Load Checks
Axial load is the force that travels along a truss member. It may pull the member in tension. It may push the member in compression. This calculator helps you review both cases. It is useful for roof trusses, floor trusses, bridge bracing, towers, and temporary works.
Why Axial Force Matters
A truss works well when loads move through straight members. Each member should mainly carry axial force. Bending should stay small. If the axial demand is high, the member may yield, buckle, or deform too much. A simple force check can prevent weak member choices. It also helps compare steel, timber, and aluminum sections.
Inputs That Improve Accuracy
The best result starts with clear units. Enter a signed known axial load when analysis is already complete. Use the angle option when a force is applied at a known angle to the member. Use the vector option when force components and member direction are known. Add area, length, radius of gyration, modulus, yield strength, effective length factor, and safety factor. These values define stress and stability.
Tension And Compression Review
Tension members are usually checked by stress and yield strength. Compression members need extra care. Slender members can buckle before the material reaches yield. The calculator estimates slenderness, Euler critical stress, critical load, and capacity using your safety factor. It also gives utilization ratios. A ratio below one is usually acceptable for the entered assumptions.
Construction Use
Use this tool during early sizing, field checks, and comparison studies. It does not replace a project code, connection design, load combinations, or licensed engineering judgment. Real trusses also need joint checks, eccentricity review, bracing, load path review, and serviceability checks. Treat the output as a planning aid. Confirm final member sizes with applicable standards and project drawings.
Good Practice
Run separate checks for dead, live, wind, and combined loads. Keep compression members well braced. Verify that the radius of gyration matches the weak axis. Review connections because they transfer the axial force. Save the CSV or PDF report for records. Recheck values when material grade, length, support condition, or load path changes.
Document assumptions clearly, so later reviewers understand each result. Use conservative values when site data is uncertain.