Tunnel squeezing is one of the major geological disasters that often occur during the construction of tunnels in weak rock masses subjected to high in situ stresses. It could cause shield jamming, budget overruns, and construction delays and could even lead to tunnel instability and casualties. erefore, accurate prediction or identification of tunnel squeezing is extremely important in the design and construction of tunnels. is study presents a modified application of a multiclass support vector machine (SVM) to predict tunnel squeezing based on four parameters, that is, diameter (D), buried depth (H), support stiffness (K), and rock tunneling quality index (Q). We compiled a database from the literature, including 117 case histories obtained from different countries such as India, Nepal, and Bhutan, to train the multiclass SVM model. e proposed model was validated using 8-fold cross validation, and the average error percentage was approximately 11.87%. Compared with existing approaches, the proposed multiclass SVM model yields a better performance in predictive accuracy. More importantly, one could estimate the severity of potential squeezing problems based on the predicted squeezing categories/classes.

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In order to study the seepage problem of the slope, the seep/w module in geo-studio is used to analyze the sluice of the Tanzhuang reservoir dam in Liaocheng, and the finite element simulation analysis of the slope seepage under different working conditions is obtained. A series of physical quantities such as seepage velocity, seepage flow and saturation line under working conditions. At the same time, the influence of different anti-seepage materials on the seepage of the slope is analyzed. The best combination of anti-seepage effect and economic benefit is obtained. The analysis results show: (1) In terms of anti-seepage effect: Compared with no anti-seepage measures, horizontal anti-seepage can reduce the seepage velocity to 81% before, and the anti-seepage effect is ideal. The vertical anti-seepage effect in the joint action with horizontal anti-seepage is extremely significant, and the seepage velocity can be reduced to 78% before. (2) In terms of project cost: The price of the anti-seepage film is relatively low, but the laying area is large, which requires a lot of manpower and material resources. The pouring concrete anti-seepage wall has a higher cost and the construction is more complicated. For this project, laying an anti-seepage film is more economical. (3) Comprehensive view: In order to combine the anti-seepage effect with the economic benefit, the combined action of the anti-seepage membrane and the anti-seepage wall is the best choice, and joint anti-seepage can be carried out at important parts, and only horizontal anti-seepage can be performed at the secondary position. The results of this study can provide reference for the same type of project, reduce construction costs, and further improve the stability of the slope.

The effective stress of the soil decreases and the pore water stress increases under the earthquake, which causes the sand to liquefy. The vertical deformation of the ground caused by the liquefaction of sand causes serious damage to the ground and the buried structure, which seriously threatens the safety of underground lifeline engineering. In order to study the impacts of sand liquefaction, the language FORTRAN was used to establish a finite element model under the earthquakes. The floating of various locations of the underground structure under different earthquakes was studied, and the factors affecting the floating were discussed. The results show that during the earthquake, the liquefaction of sand occurs, which causes the underground structure moves up due to buoyancy, and the soil mass from the structure collapses. The liquefied sand diffuses to the surrounding area after the earthquake, causing the sand beneath the underground structure to be lost, and the building will return to its original position or even collapse. The results provide references for the anti-floating research of underground structures.