# A Simple Estimation Method of Weibull Modulus and Verification with Strength Data
## 4 Material Strength Data
### Fibers
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Fibers** & **c0\textgreater{}** & **S** & **c0\textgreater{}/SD** & **m\textgreater{}obs** & **m\textless{}nt** & **N** & **m\textgreater{}obs/m\textless{}nt** & **Note** & **D/V** & **Ref** \\ \hline C fiber T800 HB & 964.0 & 152.0 & 6.34 & 6.90 & 6.98 & 20 & 0.999 & Compressive strength & V & [80] \\ C fiber M40B & 2470.0 & 390.0 & 6.33 & 6.80 & 6.97 & 20 & 0.976 & Tensile strength & V & [79] \\ C fiber M40B & 807.0 & 113.0 & 7.14 & 7.81 & 7.86 & 20 & 0.994 & Compressive strength & V & [80] \\ C fiber M60 JB & 3380.0 & 630.0 & 5.37 & 5.80 & 5.90 & 20 & 0.983 & Tensile strength & V & [79] \\ C fiber M60 JB & 999.0 & 145.0 & 6.89 & 7.57 & 7.58 & 20 & 0.999 & Compressive strength & V & [80] \\ C fiber T850 & 4211.0 & 675.0 & 6.24 & 6.55 & 6.86 & 20 & 0.955 & Tensile strength * & V & [80] \\ C fiber IN560 & 5200.0 & 874.0 & 5.95 & 6.33 & 6.54 & 20 & 0.966 & Tensile strength * & V & [80] \\ C fiber M860 & 711.0 & 114.0 & 6.24 & 6.84 & 6.86 & 20 & 0.997 & Compressive strength & V & [80] \\ C fiber UM55 & 4733.0 & 857.0 & 55.2 & 5.83 & 6.08 & 20 & 0.960 & Tensile strength * & V & [80] \\ C fiber UM55 & 502.0 & 66.0 & 7.61 & 8.34 & 8.37 & 20 & 0.997 & Compressive strength & V & [80] \\ C fiber K135 & 3410.0 & 667.0 & 5.11 & 5.36 & 5.62 & 20 & 0.952 & Tensile strength * & V & [80] \\ C fiber K135 & 87.0 & 11.0 & 7.91 & 9.00 & 8.70 & 20 & 1.034 & Compressive strength & V & [80] \\ C fiber K13C & 3270.0 & 826.0 & 3.96 & 4.21 & 4.35 & 20 & 0.967 & Tensile strength * & V & [80] \\ C fiber K13C & 35.0 & 4.0 & 8.75 & 9.22 & 9.63 & 20 & 0.958 & Compressive strength & V & [80] \\ C fiber XX60 & 3326.0 & 626.0 & 5.31 & 5.63 & 5.84 & 20 & 0.964 & Tensile strength * & V & [80] \\ C fiber XN60 & 91.0 & 11.0 & 8.27 & 9.10 & 9.10 & 20 & 1.000 & Compressive strength & V & [80] \\ C fiber XN 90 & 3400.0 & 640.0 & 5.31 & 5.00 & 5.84 & 20 & 0.856 & Tensile strength & V & [79] \\ C fiber XN 90 & 82.0 & 10.0 & 8.20 & 8.54 & 9.02 & 20 & 0.947 & Compressive strength & V & [80] \\ Basal filter & 1440.0 & 570.0 & 2.53 & 2.90 & 2.78 & 40 & 1.044 & Tensile strength & V & [55] \\ Basalt fiber & 1840.0 & 720.0 & 2.56 & 2.80 & 2.81 & 40 & 0.996 & Homogenized & V & [55] \\ Navelt 610 fiber & 3080.0 & 348.0 & 8.85 & 10.90 & 9.74 & 50 & 1.120 & Tensile strength & V & [70] \\ Navelt 720 fiber & 1964.0 & 287.0 & 6.84 & 8.10 & 7.53 & 50 & 1.076 & Tensile strength & V & [70] \\ Navelt 720 fiber & 1940.0 & 310.0 & 6.26 & 6.90 & 6.88 & 115 & 1.002 & Tensile strength & V & [71] \\ Navelt 720 fiber & 1880.0 & 300.0 & 6.27 & 6.87 & 6.89 & 53 & 0.997 & Tensile strength & V & [71] \\ Navelt 720 fiber & 1750.0 & 310.0 & 5.65 & 6.09 & 6.21 & 72 & 0.981 & Tensile strength & V & [71] \\ Navelt 720 fiber & 1710.0 & 220.0 & 7.77 & 8.90 & 8.55 & 50 & 1.041 & Tensile strength & V & [71] \\ Navelt 720 fiber & 1620.0 & 280.0 & 5.79 & 5.99 & 6.36 & 19 & 0.941 & Tensile strength & V & [71] \\ Navelt 720 fiber & 1428.0 & 168.0 & 8.50 & 10.30 & 9.35 & 51 & 1.102 & Tensile strength & V & [71] \\ Navelt 720 fiber & 1880.0 & 300.0 & 6.27 & 6.86 & 6.89 & 86 & 0.995 & Tensile strength & V & [71] \\ SiCN fibers & 9520.0 & 254.0 & 3.75 & 4.12 & 50 & 1.108 & Tensile strength & V & [81] \\ SiCN fibers & 1001.0 & 256.0 & 3.91 & 4.46 & 4.30 & 50 & 1.037 & Tensile strength & V & [81] \\ SiCN fibers & 1113.0 & 223.0 & 4.99 & 6.02 & 5.49 & 50 & 1.097 & Tensile strength & V & [81] \\ SiCN fibers & 7470.0 & 91.0 & 8.21 & 9.96 & 9.03 & 50 & 1.103 & Tensile strength & V & [81] \\ SiCN fibers & 1268.0 & 187.0 & 6.78 & 7.96 & 7.46 & 50 & 1.067 & Tensile strength & V & [81] \\ SiCN fibers & 802.0 & 110.0 & 7.29 & 8.86 & 8.02 & 50 & 1.105 & Tensile strength & V & [81] \\ \hline \hline \end{tabular}
\end{table} 
Table 5: _Cont._  
One of the reasons that fiber m values are low is the variation of fiber diameter along the length. Some studies have considered diametral effects [86; 87], but it is difficult to separate them in general. Due to the high strength levels that fibers achieve, extremely small flaws can induce fracture [88; 89].