Stress Ratio (R) & Sine Load Visualizer
Enter σmin and σmax. The tool computes R = σmin / σmax, σm = (σmax + σmin)/2, and σa = (σmax − σmin)/2, then draws the sinusoidal stress-time history.
Inputs
Results
R = σmin / σmax
-1.0000
σa (alternating)
100.000
σm (mean)
0.000
σmax / σmin
100.000 / -100.000
Notes: R = −1 → fully reversed; R = 0 → zero-to-tension; R = 1 → static load (no reversal).
Fatigue context
- The sinusoid assumes σ(t) = σm + σa·sin(ωt).
- σa = (σmax − σmin)/2 and σm = (σmax + σmin)/2.
- The stress ratio R = σmin / σmax is commonly used to select appropriate S–N or Goodman/Haigh corrections.
- Use this page to set up load cases before life calculations on the Goodman page.
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