The determination of a factor of safetymust also take into account such matters as the following:
1. Probability of accidental over-loadingof the structure by loads that exceed the design loads;
2. Types of loads (static or dynamic);
3. Whether the loads are applied once orare repeated;
4. How accurately the loads are known;
5. Possibilities for fatigue failure;
6. Inaccuracies in construction;
7. Variability in the quality of workmanship;
8. Variations in properties of materials;
9. Deterioration due to corrosion or otherenvironmental effects;
10. Accuracy of the methods of analysis;
11. Whether failure is gradual (amplewarning) or sudden (no warning);
12. Consequences of failure (minor damageor major catastrophe);
13. And other such considerations.
Ifthe factor of safety is too low, the likelihood of failure will be high and thestructure will be unacceptable; if the factor is too large, the structure willbe wasteful of materials and perhaps unsuitable for its function (for instance,it may be too heavy).
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