1. What is Truss Axial Force?

The axial force in a truss member is the internal force acting along the longitudinal axis of the member. It's calculated as the product of the reaction force and the length ratio of the truss member.

2. How Does the Calculator Work?

The calculator uses the axial force equation:

Where:

• \( \text{Reaction} \) — Support reaction force in Newtons (N)
• \( \text{Length Ratio} \) — Ratio of member length to reference length (unitless)

Explanation: The equation calculates the internal force in a truss member based on the external reaction forces and the geometry of the truss.

3. Importance of Axial Force Calculation

Details: Calculating axial forces is essential for truss design, as it determines the required member sizes and connections to ensure structural integrity and safety.

4. Using the Calculator

Tips: Enter the reaction force in Newtons and the length ratio (unitless). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical length ratio in truss analysis?
A: Length ratios typically range from 0.5 to 2.0, depending on the truss geometry and member positioning.

Q2: How do I determine the reaction force?
A: Reaction forces are calculated from the external loads on the truss using equilibrium equations (ΣFy = 0, ΣM = 0).

Q3: What's the difference between compression and tension in truss members?
A: Compression members are being squeezed (negative axial force), while tension members are being pulled (positive axial force).

Q4: Are there limitations to this simplified calculation?
A: This assumes ideal pinned joints and loads only at joints. For more complex cases, full structural analysis may be needed.

Q5: How does this relate to member sizing?
A: The axial force is used with material properties to determine the required cross-sectional area to prevent buckling (compression) or yielding (tension).