*6.3. Distribution Fitting to Reliability Results*

The reliability results presented above can be used to determine reliability models by fitting probability distributions to these estimates. In this regard, log-normal distribution and Weibull distribution for the 79 MPa stress with 5% variability in load are used. The distribution fitting includes linearizing the reliability function, plotting of linearized reliability function, and finally estimating the distribution parameters. The log-normal distribution parameters are μ and σ, whereas, the Weibull distribution parameters are β and θ. For brevity, the procedure to obtain fitted models is introduced here briefly and the details are presented elsewhere [8]. The results for log-normal distribution and Weibull distribution fitted to reliability estimates are presented in Figures 24 and 25, respectively.

The equations of fitted models are also included to determine the distribution parameters, which are summarized in Tables 6 and 7.

**Figure 24.** Log-Normal distribution fitted to reliability estimates with load-induced stress 79 MPa.

**Figure 25.** Weibull distribution fitted to reliability estimates with load-induced stress 79 MPa.




**Table 7.** Weibull distribution parameters fitted to reliability estimates.
