# Seismic Stability of Dual Tunnels in Cohesive-Frictional Soil Subjected to Surcharge Loading
## 6 Design Tables  
Tables 1-4 present the predictions of seismic bearing capacity factor of double tunnels in cohesion-frictional soil from AFELA. For convenience, boldface numbers are employed to express the minimum critical interaction distance for each case. In addition, readers can identify the probable failure patterns by these boldface numbers. The failure patterns for cases above the boldface numbers are cross-shaped failures or half-cross-shaped failures. Additionally, the failure patterns for the remaining cases are all single sided-wall failures. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & & \multicolumn{4}{c}{\(\gamma\)D/\(c\) = 0} & \multicolumn{4}{c}{\(\gamma\)D/\(c\) = 1} \\ \cline{3-10} H/D & \multirow{2}{*}{S/D} & \multicolumn{4}{c}{\(\varphi\)} \\ \cline{3-10}  & & 5\({}^{\circ}\) & 10\({}^{\circ}\) & 15\({}^{\circ}\) & 20\({}^{\circ}\) & 5\({}^{\circ}\) & 10\({}^{\circ}\) & 15\({}^{\circ}\) & 20\({}^{\circ}\) \\ \hline  & 1.5 & 3.66 & 4.79 & 6.64 & 9.91 & 0.13 & 0.84 & 2.03 & 4.34 \\  & 2 & 3.68 & 4.78 & 6.57 & 9.82 & 0.15 & 0.89 & 2.18 & 4.62 \\  & 2.5 & 3.79 & 4.94 & 6.76 & 10.06 & 0.25 & 1.08 & 2.50 & 5.15 \\  & 3 & 3.93 & 5.12 & 7.06 & 10.54 & 0.42 & 1.37 & 2.97 & 5.94 \\  & 3.5 & 4.09 & 5.39 & 7.50 & 11.39 & 0.59 & 1.67 & 3.49 & 6.97 \\  & 4 & 4.26 & 5.67 & 8.03 & 12.39 & 0.76 & 1.97 & 4.23 & 8.02 \\  & 4.5 & 4.43 & 5.96 & 8.54 & 13.49 & 0.94 & 2.28 & 4.61 & 9.09 \\  & 5 & 4.62 & 6.27 & 9.10 & 14.55 & 1.12 & 2.59 & 5.18 & 10.28 \\  & 5.5 & 4.79 & \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & & \multicolumn{4}{c}{\(\gamma\)D/\(c\) = 0} & \multicolumn{4}{c}{\(\gamma\)D/\(c\) = 1} \\ \cline{3-10} H/D & S/D & \multicolumn{4}{c}{\(\varphi\)} & \\ \cline{3-10}  & & 5\({}^{\circ}\) & **10\({}^{\circ}\)** & **15\({}^{\circ}\)** & **20\({}^{\circ}\)** & **5\({}^{\circ}\)** & **10\({}^{\circ}\)** & **15\({}^{\circ}\)** & **20\({}^{\circ}\)** \\ \hline  & 1.5 & 3.59 & 4.70 & 6.49 & 9.70 & 0.12 & 0.82 & 1.99 & 4.20 \\  & 2 & 3.61 & 4.68 & 6.45 & 9.64 & 0.14 & 0.87 & 2.13 & 4.55 \\  & 2.5 & 3.72 & 4.83 & 6.64 & 9.88 & 0.23 & 1.06 & 2.44 & 5.07 \\  & 3 & 3.84 & 5.02 & 6.93 & 10.34 & 0.39 & 1.32 & 2.90 & 5.81 \\  & 3.5 & 4.00 & 5.28 & 7.36 & 11.19 & 0.55 & 1.60 & 3.42 & 6.80 \\  & 4 & 4.18 & 5.55 & 7.86 & 12.12 & 0.72 & 1.90 & 3.95 & 7.80 \\  & 4.5 & 4.34 & 5.84 & 8.36 & 13.22 & 0.89 & 2.20 & 4.47 & 8.98 \\  & 5 & 4.52 & 6.14 & 8.93 & 14.38 & 1.05 & 2.50 & 5.05 & 10.08 \\  & 5.5 & 4.69 & 6.42 & 9.49 & 15.51 & 1.21 & 2.78 & 5.58 & 11.23 \\  & 6 & 4.85 & 6.71 & 10.02 & 16.76 & 1.37 & 3.05 & 6.11 & 12.37 \\  & 6.5 & 5.00 & 6.98 & 10.57 & 17.97 & 1.52 & 3.26 & 6.38 & 13.18 \\
3 & 7 & 5.13 & 7.22 & 11.06 & 19.28 & 1.62 & 3.33 & 6.53 & 13.36 \\  & 7.5 & 5.18 & 7.30 & 11.28 & 19.55 & 1.67 & 3.40 & 6.63 & **13.48** \\  & 8 & 5.22 & 7.38 & 11.38 & 19.70 & 1.71 & 3.45 & **6.70** & 13.48 \\  & 8.5 & 5.25 & 7.42 & 11.44 & 19.73 & 1.74 & 3.46 & 6.70 & 13.48 \\  & 9 & 5.28 & 7.47 & 11.48 & **19.76** & 1.79 & **3.48** & 6.70 & 13.47 \\  & 9.5 & 5.30 & 7.51 & **11.50** & 19.76 & 1.80 & 3.48 & 6.70 & 13.48 \\  & 10 & 5.32 & **7.54** & 11.50 & 19.76 & **1.81** & 3.48 & 6.70 & 13.48 \\  & 10.5 & **5.34** & 7.54 & 11.51 & 19.76 & 1.81 & 3.48 & 6.71 & 13.48 \\  & 11 & 5.34 & 7.54 & 11.50 & 19.75 & 1.81 & 3.48 & 6.70 & 13.48 \\  & 12 & 5.34 & 7.54 & 11.50 & 19.76 & 1.81 & 3.48 & 6.70 & 13.48 \\ \hline \hline \end{tabular}
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