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A laboratory model test of tunnel anchor was conducted to investigate its pullout mechanism and bearing capacity. Surface and rock deformation, strain and stress were measured during the entire model test process. The results show that: under pull out load, tensile failure first occurs in top surface rock near the anchor, then shear failure occurs in anchor-rock interface and rock around the anchor. The failure surface is inverted cone from the anchor bottom. Under 50 times design cable force tunnel rock is in elastic stage, suggesting that current tunnel anchor design is quite conservative and can be further optimized.

With the geographic information technology in a wide range of applications in geotechnical engineering, in geotechnical engineering, the computer visualization technology has also been rapid development. Accurate three-dimensional mathematical model can make exploration data more realistic. In this paper, the three-dimensional visualization technology of computer combined with mathematical elevation model (DEM), and using multi-faceted function interpolation method to establish the accurately and effectively three-dimensional digital model of the slope. The results show that, the use of multi-faceted function interpolation method can effectively solve the slope of three-dimensional digital modeling interpolation problem.

Zn20Sn6Cu solder with the melting point of 382°C has good mechanical properties and low cost. Therefore it is considered as an ideal high-temperature lead-free solder. However, its physical properties and spreading properties are poor. In this paper a new solder was made by adding trace LaNd into Zn20Sn6Cu alloy to improve the performance. The effect of the content of LaNd on physical properties and weld ability of Zn20Sn6Cu solder was investigated. The experimental results showed that the effect of the content of LaNd on the melting point of Zn20Sn6Cu solder was not obvious and the liquid-solid temperature range of the Zn20Sn6Cu solder increased with the increasing of the content of LaNd (less than 0.5 wt.%). When RE content was 0.1 wt.%, the liquid-solid temperature range of Zn20Sn6Cu0.1RE was only 13.3°C. The resistivity of the novel solders increased with the increasing of the content of LaNd. When LaNd is higher than 0.3 wt%, the resistivity of the novel solder sharply increased. The spreading performance of the new solder alloy was improved obviously by adding trace LaNd into Zn20Sn6Cu solder. When the content of LaNd was 0.1 wt%, the spreading area of Zn20Sn6Cu0.1LaNd solder reached to the maximum value of 32.5% bigger than that of the matrix solder, which mainly related to the formation of the new CuZn5 and Cu5Zn8 phases as well as the intermetallic compounds between the solder and the substrate. Therefore, considering the physical properties and spreading properties of the novel solders, the best content of LaNd is about 0.1 wt.%.