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The landslide at the entrance of a railway tunnel is large scale, and serious diseases are prone to appear under natural disasters, which threaten the safety of the tunnel. According to its characteristics, on-site long-term monitoring experiments and numerical analysis were carried out, and the mechanism of interaction between landslide and tunnel engineering was analyzed. The results show that under the impact of rainfall and earthquake, the original internal stress balance in the landslide body is disturbed, leading to the increase in landslide thrust and damage of the tunnel lining. Simultaneously, the excavation of the tunnel can slack the surrounding rock to increase the landslide thrust and make the landslide be finally formed; this landslide conversely acts on the tunnel, resulting in deformation and destruction of the tunnel. During the monitoring, under the influence of rainfall and earthquake, the stress of the secondary lining was continuously increased by 25%. Tunnel construction caused a maximum deformation of 30 mm in the antislide pile at a distance of 2.12 m, and the slope and the tunnel were also affected. Under extreme conditions such as rainfall and earthquake, shear failure occurred at the vault, bottom, and waist of the right-line tunnel located at the junction of soil and rock; at this time, the tensile strength of the tunnel reached 93.8% of the limit value of concrete, which seriously affected the safety of the tunnel. As for the weakened tunnel structure, measures such as dense planting and strengthening of concrete strength should be adopted to enhance the safety of the tunnel structure.

With the vigorous development of China’s railroad industry, increased railroad construction has extended to complex and dangerous mountainous areas. During the construction and operation of railroads in this area, various geological disasters are inevitable, bringing significant difficulties to railroad construction and significant threats to personal safety. This study focuses on the typical railroad passing through dense and dangerous mountainous areas as the research object. Through on-site investigations, the characteristics of slope disasters along the railroad were analyzed following the laws of disaster distribution and characteristics of disaster development. The study analyzes the causes of slope disasters by investigating internal and external factors. The research results show that the geological disasters along the railroad can be divided into landslides and collapses, of which there are 8 landslide disasters and 15 collapse catastrophes. Landslides are characterized as creeping and fretting stages according to their development characteristics. Collapses can be divided into four types of dangerous rock masses according to the scale of disaster distribution. Many factors influence the development of landslide geological disasters, and the development of geological disasters is the result of the combined action of multiple influencing factors. By analyzing the slope disaster along the railroad, this study provides an effective reference basis for constructing complex mountain railroads in the future.

Landslide is one of the most widely distributed and most severe geological hazards among the types of slope damage. China is among the countries most seriously affected by landslide disasters in the world. The unreasonable landslide anti-slide design will not only miss the best time for landslide treatment but also cause unnecessary engineering waste. Some may even worsen slope deformation and damage. Thus, reasonable slope protection and reinforcement and landslide anti-slide engineering design have become the current research fascination. This paper uses the Chengdu–Lanzhou Railway as the research object. This railway exhibits the typical characteristics of “four poles and three heights” in engineering geology. The main geological hazards and typical geological conditions of the Chengdu–Lanzhou Railway are systematically explained. The reasons for the determination of the principal axis section of the most unfavorable landslide and the basis for the determination of the sliding surface are summarized. Moreover, in this paper, a reasonable anti-slide engineering design is proposed. Finally, the friction coefficient of the main sliding section is calculated using the method of the coefficient of stability of the block, and the landslide thrust is calculated. Then, the stability coefficient of the landslide is verified using the GEO-Slope limit equilibrium method to determine whether the anti-slide engineering design is reasonable. This article provides a more scientific anti-skid engineering design idea and a scientific analysis method for the rationality of anti-skid engineering design.

In order to obtain waterborne two-component polyurethane (WB 2K-PUR) with good mechanical properties as well as excellent corrosion resistance, a series of hydroxyl-based polyurethane (HO-WPU) were synthesized using isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA), and different proportions of polyether polyol (PTMEG) and polyester polyol (P1012) in this paper. Then WB 2K-PUR coatings were prepared with water-dispersible isocyanates (WDPI) as curing agent. The influence of the proportion of polyester polyols and polyether polyols in soft segments on coatings properties was studied. The characteristics of the coatings were analyzed by Fourier transform infrared spectroscopy (ATR-IR), contact angle, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and atomic force microscopy (AFM). The results showed that the mechanical properties and corrosion resistance of polyester and polyether polyols with appropriate proportion are improved significantly. The mechanism tended to be that with the addition of polyester, more hydrogen bonds were formed between the molecules, which increased the compactness of the coating as a physical crosslinking point. However, the ester groups have a strong affinity to water molecules, so the hydrophilicity of the coating was increased by excessive polyester polyols, and the shielding effect on the corrosion medium was reduced. With the inclusion of 40 % (g/g) P1012 in polyols, the coating has satisfied comprehensive properties.