# Development of Rock Embedded Drilled Shaft Resistance Factors in Korea based on Field Tests
## 3 Determination of Resistance Factors
### Determination of Statistical Parameters
#### 3.1.2 Resistance Statistics
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multirow{3}{*}{**Shaft No.**} & \multirow{3}{*}{**Depth**} & \multirow{3}{*}{**Measured**} & \multirow{3}{*}{**Error \& **[PERSON] (1988)**} & \multirow{3}{*}{**[PERSON] \& [PERSON] (1979)**} & \multirow{3}{*}{**[PERSON] (1999)**} & \multirow{3}{*}{**[PERSON] \& [PERSON] (1987)**} \\ \cline{3-3} \cline{5-10}  & & & **Shaft** & & & & & & & \\ \cline{3-3} \cline{5-10}  & & & **Resistance** & **Resistance** & **Resistance** & **Resistance** & **Resistance** & **Resistance** & **Resistance** & **Resistance** \\ \cline{3-3} \cline{5-10}  & & & **(MPa)** & & & & & & & \\ \hline \multirow{3}{*}{TP1} & 35.0–36.0 & 1.22 & 0.36 & 1.53 & 0.38 & 1.44 & 0.36 & 1.51 & 0.83 & 0.66 \\ \cline{3-3} \cline{5-10}  & 36.0–37.0 & 2.45 & 0.80 & 3.18 & 0.85 & 2.99 & 0.81 & 3.15 & 1.84 & 1.38 \\ \cline{3-3} \cline{5-10}  & 37.0–38.7 & 1.90 & 0.77 & 2.09 & 0.82 & 1.96 & 0.78 & 2.07 & 1.77 & 0.91 \\ \hline \multirow{3}{*}{TP2} & 28.8–32.9 & 0.81 & 0.89 & 0.9 & 0.95 & 0.85 & 0.90 & 0.89 & 2.06 & 0.39 \\ \cline{3-3} \cline{5-10}  & 32.9–33.9 & 0.89 & 0.77 & 1.16 & 0.82 & 1.09 & 0.78 & 1.14 & 1.77 & 0.5 \\ \cline{3-3} \cline{5-10}  & 33.9–35.3 & 2.06 & 1.03 & 2 & 1.10 & 1.88 & 1.04 & 1.98 & 2.37 & 0.87 \\ \hline \multirow{3}{*}{TP3} & 26.9–28.0 & 0.68 & 0.57 & 1.19 & 0.61 & 1.12 & 0.58 & 1.18 & 1.32 & 0.52 \\ \cline{3-3} \cline{5-10}  & 28.0–29.0 & 0.37 & 0.65 & 0.57 & 0.69 & 0.54 & 0.66 & 0.56 & 1.50 & 0.25 \\ \cline{3-3} \cline{5-10}  & 29.0–30.0 & 1.40 & 0.82 & 1.7 & 0.88 & 1.6 & 0.83 & 1.69 & 1.90 & 0.74 \\ \cline{3-3} \cline{5-10}  & 30.0–31.0 & 1.79 & 0.81 & 2.21 & 0.86 & 2.08 & 0.82 & 2.19 & 1.86 & 0.96 \\ \cline{3-3} \cline{5-10}  & 31.0–33.1 & 2.69 & 0.67 & 4.02 & 0.71 & 3.78 & 0.68 & 3.98 & 1.54 & 1.74 \\ \hline \multirow{3}{*}{TP4} & 24.0–30.5 & 0.24 & 0.27 & 0.87 & 0.29 & 0.82 & 0.28 & 0.86 & 0.63 & 0.38 \\ \cline{3-3} \cline{5-10}  & 44.0–46.5 & 0.32 & 2.18 & 0.15 & 2.32 & 0.14 & 2.20 & 0.15 & 5.01 & 0.06 \\ \cline{3-3} \cline{5-10}  & 46.5–48.5 & 2.85 & 2.58 & 1.1 & 2.75 & 1.04 & 2.61 & 1.09 & 5.95 & 0.48 \\ \cline{3-3} \cline{5-10}  & 48.5–50.5 & 2.00 & 2.85 & 0.7 & 3.03 & 0.66 & 2.88 & 0.69 & 6.56 & 0.3 \\ \cline{3-3} \cline{5-10}  & 50.5–52.5 & 1.44 & 2.67 & 0.54 & 2.84 & 0.51 & 2.69 & 0.54 & 6.14 & 0.23 \\ \cline{3-3} \cline{5-10}  & 52.5–54.5 & 1.52 & 1.26 & 1.2 & 1.34 & 1.13 & 1.27 & 1.19 & 2.90 & 0.52 \\ \hline \multirow{3}{*}{TP7} & 45.5–50.21 & 3.35 & 1.36 & 2.46 & 1.45 & 2.31 & 1.37 & 2.44 & 3.13 & 1.07 \\ \cline{3-3} \cline{5-10}  & 46.26–48.26 & 1.22 & 0.28 & 4.36 & 0.30 & 4.1 & 0.28 & 4.32 & 0.64 & 1.89 \\ \cline{3-3} \cline{5-10}  & 48.26–49.76 & 1.17 & 0.38 & 3.04 & 0.41 & 2.85 & 0.39 & 3.01 & 0.88 & 1.32 \\ \cline{3-3} \cline{5-10}  & 49.76–51.35 & 1.60 & 0.55 & 2.9 & 0.59 & 2.73 & 0.56 & 2.87 & 1.27 & 1.26 \\ \hline \end{tabular}
\end{table} 
Table 6: Calculated bias factors for shaft resistance. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{2}{c}{**Load Factor of Dead Load (\(\gamma_{\text{D}}\)=1.25)**} & \multicolumn{2}{c}{**Load Factor of Live Load (\(\gamma_{\text{L}}\)=1.75)**} \\ \hline
**Mean (\(\lambda_{\text{D}}\))** & **CoefficientofVariation (COV\({}_{\text{D}}\))** & **Mean (\(\lambda_{\text{L}}\))** & **CoefficientofVariation (COV\({}_{\text{L}}\))** \\ \hline
1.05 & 0.10 & 1.15 & 0.20 \\ \hline \end{tabular}
\end{table} 
Table 5: Statistical characteristics of the loads. These calculated bias factors were then used to determine the resistance statistics, such as the mean, standard deviation, and coefficient of variation. These resistance statistics are summarized in Table 9. In this procedure, extremely outlying data points may not be representative of the resistance due to some large error; therefore, the bias factor values outside the boundary defined by the mean plus two times the standard deviation were omitted according to [PERSON] [28]. In case of [PERSON] & [PERSON], statistics based on all data were calculated as follows; mean as 1.55, Standard deviation as 1.11, and COV as 0.72.