1. Shih-Hao Lee IUFRO Division 5 Conference 5.02.00 B Mechanical Properties of Wood Poster #392

2. National Chiayi University Department and Graduate Institute of –Forest Products Science #300 University Road Chiayi 600 Taiwan, ROC Shih-Hao Lee Estimation of Weibull Parameters for Fracture Toughness of oak Chiayi Taipei, Taiwan

3. Development of Weibull function’s Parameters. Exploratory case study with qualitative and quantitative methodology. Aim of work and methods To assess the reliability of wood structures To estimate the two-, (scale, shape), and three- parameter, (location, scale, shape), Weibull functions and compare their performance.

4. Results Figure 1. The two-parameter Weibull functions The two-parameter and three- parameter Weibull functions were estimated Figure 2. The three-parameter Weibull function Weibull functions location scaleshapedetermination coefficient two- parameter 027210.60.96 three- parameter 17792.63.020.97 Table 1. parameters of Weibull functions and determinationcoefficient.

5. In this study, three-parameter and two- parameter Weibull functions were successfully estimated. Coefficient of determination, r 2, of three parameter Weibull function is closer to 1 than that of two parameter Weibull function. The importance of selection of proper distribution is evident. Conclusions