Safety Factors and Reliability Estimates

To highlight the need and the impact of the statistically based considerations, safety factor (S.F.) is now defined on the basis of the mean and some selected minimum property (eg., allowable design strength). 

X is associated with some probability for failure, which depends on the choice of the distribution function. For illustration, (a) the influence in choice of the distribution function is considered in terms of the Normal (or Gaussian) and the Weibull distributions, and (b) the influence of sample size is examined using the Normal distribution. 

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