## 4 Instance Analysis
### Construction Design  
In landslide geological disaster control measures, anti-slide pile is widely used in landslide control because of its strong anti-slide ability, wide application conditions and good control effect. Therefore, according to the engineering examples in this paper, single-row full-length, double-row full-length and double-row buried anti-slide piles are selected, \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Stratum**} & \multicolumn{3}{c}{**Natural Condition**} & \multicolumn{3}{c}{**Saturation Condition**} \\ \cline{2-7}  & \(\boldsymbol{\gamma\) (kN/m3)} & **C (kPa)** & \(\boldsymbol{\Phi}\) (\({}^{\circ}\)) & \(\boldsymbol{\gamma\) (kN/m3)} & **C (kPa)** & \(\boldsymbol{\Phi}\) (\({}^{\circ}\)) \\ \hline Malan loess & 19.5 & 13.5 & 19.5 & 20.1 & 9.8 & 13.0 \\ Paleosol & 19.6 & 18.0 & 20.0 & 20.2 & 15.0 & 10.0 \\ Lishi Loess & 19.9 & 15.0 & 23.0 & 20.3 & 10.2 & 15.0 \\ Paleosol & 19.4 & 18.0 & 20.0 & 20.3 & 15.0 & 10.0 \\ Lishi Loess & 19.9 & 15.0 & 23.0 & 20.4 & 10.2 & 15.0 \\ Slipband & 19.7 & 13.0 & 12.0 & 21.9 & 10.0 & 10.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of experimental results and index parameters of each soil layer of landslide. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Selection Condition**} & \multirow{2}{*}{**Stability Coefficient**} & \multicolumn{2}{c}{**Surplus Sliding**} \\  & & **Force (KN/m)** & **Steady State** \\ \hline Condition 1 & 1.387 & 1900 & stabilization \\ Condition 2 & 1.089 & 1711 & understable \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Stability calculation results. respectively, for landslide design, and the safety factor and engineering quantity after treatment are calculated to select the optimal treatment scheme. (1) Single row of full-length anti-slide piles. When a single row of full-length anti-slide piles is used for landslide treatment, the round-section mechanically drilled anti-slide piles are adopted. In order to meet the strength requirements, the pile diameter should be 4.0 m, the pile spacing between two adjacent piles is 8.0 m and the pile length of the load section of the pile body is the same as the thickness of the slide body, which is 26.0 m. The pile bottom is buried 8.0 m below the bedrock surface, the total length of anti-slide piles is 34.0 m and a total of 36 piles are arranged. At this time, the transfer coefficient method recommended in the Technical Code for Design and Construction of Landslide Prevention Engineering, that is, Formulas (1) and (2), can be used to calculate the stability coefficient when a single row of full-length anti-slide piles is set, and the calculation process can be realized by normal rock and soil software. The calculated stability coefficient is 1.2 (less than the specified design safety factor 1.3), and engineering quantity of landslide control is 15,373 m\({}^{3}\). It can be seen that the cost is high, the retaining effect is not ideal and the reinforcement does not meet the structural requirements because of the large section of the single-row full-length anti-slide pile. Therefore, the use of double-row full-length anti-slide piles is considered. (2) Double row of full-length anti-slide piles. If double rows of full-length anti-slide piles are used for treatment, the anti-slide piles used in this treatment project are circular anti-slide piles with a diameter of 2.5 m according to the principle of structural design, and the spacing between two adjacent piles is 5.0 m, and the spacing between rows is 5.0 m. The length of load section and anchorage section of pile body is the same as that of single row, and the tops of front and back anti-slide piles are level with the ground, and the number of anti-slide piles is 72. Under this design condition, the stability coefficient is 1.3 (it is equal to the safety factor value 1.3 stipulated in the Technical Code for Design and Construction of Landslide Control Engineering) and the engineering quantity is 12,717 m\({}^{3}\).