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　　Two research projects completed by China Railway Academy Co., Ltd. have passed evaluation by an expert panel, which said both had reached the international leading level. The two research projects are about the application technology of steel fiber concrete segments and the design of waterproof single-layer lining for hard-rock tunnels. 

　　A systematic study covering material mix, mechanical properties of materials, segment design, full-size test and segment production and application was made for the research project on the application technology of steel fiber concrete segments. A complete system for technology application was formed. The project innovatively put forth design methods for mixing steel fiber concrete and making segments unreinforced or partly reinforced by steel fiber concrete, and the method for distributing steel fibers in making the segments. For the first time, it made the steel fiber concrete segments crack resistant in the working condition with thrust, and solved a series of problems in the design and installation of steel fiber concrete segments. The research project has set three industry standards, obtained two invention patents, and published five academic papers. 

　　The project was focused on the design, material properties, waterproof coating, construction process and quality evaluation system for waterproof single-layer lining in hard-rock tunnels. A comparatively complete system for technology application was formed. It innovatively proposed methods to analyze the stability of hard-rock tunnels, calculate the safety of single-layer shotcrete-bolt lining structure, and design such structure. A technology set for designing waterproof single-layer lining in hard-rock tunnels was formed. It also put forth the method of mixing high-performance fiber concrete and the corresponding construction process, presented a computing model for the collaboration between the waterproof interlayer and the concrete layer, and determined the requirements for waterproof materials and corresponding construction process. It innovatively used infrared thermal imaging technology for early-stage prediction and late-stage enhancement of coating concrete. The research project has set three industry standards in design, construction and testing and acceptance, obtained three invention patents and published five papers on core academic journals.