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). ; G7 f B! F) }7 [8 i _) ~
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