The effects of Cl(-) on the corroded surface layer of 00Cr22Ni5Mo3N duplex stainless steel under cavitation in chloride solutions were investigated using nanoindentation in conjunction with XRD and XPS. The results demonstrate that Cl(-) had a strong effect on the nano-mechanical properties of the corroded surface layer under cavitation, and there was a threshold Cl(-) concentration. Furthermore, a close relationship between the nano-mechanical properties and the cavitation corrosion resistance of 00Cr22Ni5Mo3N duplex stainless steel was observed. The degradation of the nano-mechanical properties of the corroded surface layer was accelerated by the synergistic effect between cavitation erosion and corrosion. A key factor was the adsorption of Cl(-), which caused a preferential dissolution of the ferrous oxides in the passive film layer on the corroded surface layer. Cavitation further promoted the preferential dissolution of the ferrous oxides in the passive film layer. Simultaneously, cavitation accelerated the erosion of the ferrite in the corroded surface layer, resulting in the degradation of the nano-mechanical properties of the corroded surface layer on 00Cr22Ni5Mo3N duplex stainless steel under cavitation.

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The water retention curve (WRC) of a geosynthetic clay liner (GCL) is influenced by the presence of exchangeable cations in the leachate during changes in water content in a landfill construction. This research aims to investigate the impact of salinity on the WRC of GCL. To measure the WRC of GCL under different sodium chloride (NaCl) concentrations on the drying path, a chilled-mirror dew-point device capable of controlling the GCL’s volume was employed. Additionally, the dry state microstructure of the GCL was examined using electron microscopy. The test outcomes indicate that GCL hydrated with higher salinity has greater suction at the same water content during drying. This influence can be attributed to changes in salinity and the precipitation of NaCl crystals within the bentonite when water evaporates, which in turn affects the bentonite’s microstructure and leads to increased matric suction. By introducing the Fredlund and Xing model and parameter relationship, it is possible to predict the WRC of GCL under salinity effects after measuring the WRC under different salinity conditions on the drying path.

The characteristics of the vibrations induced by the passage of a high-speed train do not only depend on the train speed, axle load, and track irregularity but also depend on the properties of the foundation soil and the surrounding topography. Estimating the vibration characteristics in different terrains is therefore essential. This study investigates the characteristics of propagation and attenuation of the vibrations induced by high-speed trains in loess-terraced slopes. The influence of the soil mechanical properties on the propagation of vibrations is analyzed through a numerical simulation. Field experiments are conducted to measure the vibration induced by a high-speed train at a loess-terraced slope site in Qin’an, Gansu, China. The measured acceleration time history is analyzed in the time domain and frequency domain. The results show that, at the edge of each terrace level, the vibration in the Y direction is the strongest, followed by those in the X and Z directions. The peak ground acceleration values are amplified in all three directions at the fourth terrace level. A model describing the vehicle-roadbed-foundation-terraced slope system is established to study the influence of the elastic modulus of the soil on the vibration characteristics. A change in the elastic modulus of the foundation soil is found to have an evident influence on the horizontal and vertical vibrations in each terrace level. However, a change in the elastic modulus of the soil in a terrace only affects the vibration in that terrace and in the adjacent ones, whereas it has no effect on the vibrations in terraces located farther away. This study can provide some reference values for slope reinforcement along railways.

This study investigated the engineering properties of a rubber–bentonite mixture under different salt solution concentrations, mass ratios, and consolidation pressures. In addition, the effects of different solute ion concentrations on the compression index of the samples were compared. The results showed that the compression coefficient could be reduced effectively by increasing the weight percentage of rubber without being affected by the salt solution. However, with the increase in the salt solution concentration, the compression coefficient of mixed materials with different mass ratios increased, and when the salt solution concentration exceeded 0.5 mol/L, the compression coefficient increased more obviously. In a 0.1 mol/L NaCl solution, the addition of different levels of rubber could increase the compression modulus of the mixed material and reduce the compression ratio of the mixed material. This showed that in an environment with a low salt solution concentration, adding rubber into the mixed material could enhance its compressive deformation resistance. However, when the rubber content exceeded 50%, significant pores appeared in the sample, and the effect of high salt solution concentration intensified. The rubber content also had an effect on the swelling properties of soil, and the degradation of rubber in the salt solution showed reduced mechanical properties. This emphasizes the need to consider the stability and resistance of saline–alkali areas to salt erosion.