## 3 Review of the Design Codes
### Piled Raff Foundation Design  
A piled raft foundation is a composite construction that has recently been widely applied around the world, especially for the construction of multistory buildings/high-rise buildings, in order to (1) increase the load capacity, (2) decrease the foundation settlement, and (3) reduce the construction cost. \begin{table}
\begin{tabular}{c c c c} \hline \hline Notation & Description & Value & Notes \\ \hline \(\mathrm{B}^{\prime}\) & Effective width of the foundation (m) & 10 & - \\ \hline \(\mathrm{L}^{\prime}\) & Effective length of the foundation (m) & 20 & - \\ \hline \(\mathrm{A}^{\prime}\) & Design effective area of the & 200 & \(\mathrm{A}^{\prime}=\mathrm{B}^{\prime}\;*\mathrm{L}^{\prime}\) \\ \hline \(\mathrm{c}^{\prime}\) & Design effective cohesion (kPa) & To be calculated & - \\ \hline \multirow{3}{*}{\(\mathrm{q}^{\prime}\)} & Design effective overburden pressure at & \multirow{3}{*}{19.42} & \multirow{3}{*}{\(\mathrm{q}^{\prime}=\gamma^{\prime}\;*\mathrm{d}\)} \\  & the level of the foundation & & \\  & base (kN/m\({}^{2}\)) & & \\ \hline \(\mathrm{\gamma}^{\prime}\) & Design effective weight density of soil & \multirow{3}{*}{To be calculated} & \multirow{3}{*}{-} \\  & below the foundation level (kN/m\({}^{3}\)) & & \\ \hline \(\mathrm{N}_{\mathrm{q}}\) & & \multirow{3}{*}{\(\mathrm{N}_{\mathrm{q}}=\mathrm{e}^{\pi\tan\varphi^{\prime}}\tan^{2}\left(\frac{ \alpha}{4}+\frac{\varphi^{\prime}}{2}\right)\)} \\ \cline{3-3} \cline{5-5} N\({}_{\mathrm{c}}\) & Bearing resistance factors & & \multirow{3}{*}{To be calculated} & \(\mathrm{N}_{\mathrm{c}}=(\mathrm{N}_{\mathrm{q}}-1)\cot\varphi^{\prime}\) \\ \cline{3-3} \cline{5-5} N\({}_{\mathrm{Y}}\) & & & \(\mathrm{N}_{\mathrm{Y}}=2(\mathrm{N}_{\mathrm{q}}-1)\tan\varphi^{\prime}\) \\ \hline \(\mathrm{b}_{\mathrm{q}}\) & & \multirow{3}{*}{\(\mathrm{b}_{\mathrm{q}}=(1-\alpha\tan\varphi^{\prime})^{2}\)} \\ \cline{3-3} \cline{5-5} b\({}_{\mathrm{c}}\) & Inclination factors & & \(\mathrm{b}_{\mathrm{c}}=\mathrm{b}_{\mathrm{q}}-\left(1-\mathrm{b}_{\mathrm{q}} \right)/(\mathrm{N}_{\mathrm{c}}\tan\varphi^{\prime})\) \\ \cline{3-3} \cline{5-5} b\({}_{\mathrm{Y}}\) & & & \(\mathrm{b}_{\mathrm{y}}=(1-\alpha\tan\varphi^{\prime})^{2}\) \\ \hline \(\mathrm{s}_{\mathrm{q}}\) & & \multirow{3}{*}{\(\mathrm{s}_{\mathrm{q}}=1+\sin\varphi^{\prime}\) for a square shape} \\ \cline{3-3} \cline{5-5} s\({}_{\mathrm{c}}\) & Shape factors & To be calculated & \(\mathrm{s}_{\mathrm{c}}=\left(\mathrm{s}_{\mathrm{N}_{\mathrm{q}}}-1\right)/ \left(\mathrm{N}_{\mathrm{q}}-1\right)\) for a rectangular, square, or circular shape \\ \cline{3-3} \cline{5-5} s\({}_{\mathrm{Y}}\) & & & Equal to 0.7 for a square shape \\ \hline \(\mathrm{i}_{\mathrm{c}}\) & & \multirow{3}{*}{\(\mathrm{i}_{\mathrm{q}}=\mathrm{i}_{\mathrm{q}}-1\left(1-\mathrm{i}_{ \mathrm{q}}\right)/(\mathrm{N}_{\mathrm{c}}\tan\varphi^{\prime})\)} \\ \cline{3-3} \cline{5-5} i\({}_{\mathrm{q}}\) & & & \(\mathrm{i}_{\mathrm{q}}=\left[1-\frac{\mathrm{H}}{\mathrm{V}+\mathrm{A}^{\prime} \mathrm{c}^{\prime}\cot\varphi^{\prime}}\right]^{\mathrm{m}}\) \\ \hline \multirow{3}{*}{\(\mathrm{i}_{\mathrm{Y}}\)} & Inclination factors of the load caused by & \multirow{3}{*}{To be calculated} & \multirow{3}{*}{\(\mathrm{i}_{\mathrm{Y}}=\left[1-\frac{\mathrm{H}}{\mathrm{V}+\mathrm{A}^{\prime} \mathrm{c}^{\prime}\cot\varphi^{\prime}}\right]^{\mathrm{m}+1}\)} \\  & horizontal load H & & where: \\ \cline{3-3} \cline{5-5} i\({}_{\mathrm{Y}}\) & & & \(\mathrm{m}=\mathrm{m}_{\mathrm{B}}=[2+(\mathrm{B}^{\prime}/L)]/[1+(\mathrm{B}^{ \prime}/L)]\) where H acts in the direction of B; \\ \cline{3-3} \cline{5-5}  & & & \(\mathrm{m}=\mathrm{m}_{\mathrm{L}}=[2+(\mathrm{L}^{\prime}/B)]/[1+(\mathrm{L}^{ \prime}/B)]\) where H acts in the direction of L; \\ \hline \(\alpha\) & Inclination of the foundation base to & \multirow{3}{*}{0} & \multirow{3}{*}{-} \\  & the horizontal & & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Description of parameters in Eurocode 7.