The Ningxia Highway Construction Administration actively promotes and applies new technologies, new processes, new equipment, and new materials—the "Four New" technologies—to provide support for strengthening quality and safety control of the Liupanshan Extra-Long Tunnel on the Dongmao Expressway.

 

　　　First, new measures for quality and safety management were introduced. Technical consulting service units were brought in from outside the region, four tunnel technical experts were hired from across the country, and five tunnel consulting expert groups composed of relevant personnel from construction, contracting, supervision, and scientific research were established to "diagnose and prescribe remedies" for tunnel construction management. Second, new construction processes were actively adopted. The tunnel adopted the three-bench seven-step excavation method to ensure construction space and enable simultaneous parallel operations at multiple working faces; by adopting the top-heading construction process with the upper and lower bench method, construction time for process conversion was saved and tunnel excavation speed was accelerated. Third, new construction technologies were actively applied. An advanced geological prediction system was adopted, with various sensors installed on multifunctional drilling rigs to grasp the geological conditions of the tunnel face in real time, adjust support parameters promptly, and ensure construction safety. Fourth, new construction equipment was fully adopted. A semi-automatic waterproof board platform was introduced to improve the quality of tunnel waterproof board installation; semi-automatic shotcrete machines were fully used to spray concrete inside the tunnel, improving work efficiency; infrared automatic temperature-controlled hot-melt welding guns were effectively used to ensure effective fusion between the waterproof board and the hot-melt backing; and a plasma automatic cutting machine at the steel structure yard was used to cut steel plates, improving the connection quality of flange plates. Fifth, control methods were made information-based. Dynamic integrated management and control of on-site construction quality data was vigorously promoted, and five major systems were established: tunnel safety video monitoring, construction personnel positioning, voice calling, mixing station and laboratory data management and control, and pedestrian-vehicle separation access control. The construction site was built into an intelligent monitoring platform to achieve real-time remote video monitoring. Sixth, efforts in scientific and technological research were intensified. The administration actively undertook research topics such as the Ministry of Transport's "Large Deformation Control Technology for Water-Rich Deep-Buried Structural Soft Rock" and, together with all construction participants and relevant research institutes, carried out joint research on topics such as "Research on the Application of Long-Distance Reverse-Slope Drainage Technology in Highway Tunnels" and "Research on Drainage Control Standards and Construction Technology for Tunnels in High-Risk Ecologically Sensitive Areas."