According to China Railway International Co., Ltd., on November 16 local time in Indonesia, a high-speed railway comprehensive inspection train developed and manufactured by China Railway carried out a comprehensive inspection of the line between Dekarur Station and No. 4 Beam Yard of Ya'an Wanzhou High Speed Railway, and the obtained indicators and parameters performed well, marking the successful trial operation of the Ya'an Wanzhou High Speed Railway jointly constructed by China and Indonesia. The Jakarta Wanzhou high-speed railway connects Jakarta, the capital of Indonesia, with Bandung, the famous tourist city, with a total length of 142.3 kilometers and a maximum operating speed of 350 kilometers. It was fully started in June 2018. It is a landmark project for the construction of the "the Belt and Road" and practical cooperation between China and Indonesia. It is also the first overseas construction project of China's high-speed railway with a whole system, all elements, and a whole industrial chain. The whole line adopts Chinese technology and Chinese standards. At present, the construction of Ya'an Wanzhou High speed Railway is progressing smoothly. All 13 tunnels along the line have been completed, box girder erection has been completed, and track laying on the main line is progressing in an orderly manner; High speed EMUs and comprehensive detection trains of Ya'an Wanzhou High speed Railway have been developed; The 14 km line from Dekalur Station to No. 4 beam yard has been completed, and the hot slip test of EMU trains under the electrification of the catenary has been successfully carried out. It is reported that after the opening and operation of the Jakarta Bandung high-speed railway, the travel time of the Jakarta Bandung train will be shortened from more than 3 hours to 40 minutes, which will greatly improve the local traffic conditions, help Indonesia's economic and social development, and be of great significance for deepening practical cooperation between China and Indonesia and promoting the high-quality development of the "the Belt and Road". On November 24, 2020, Ya'an Wanzhou High speed Railway Tunnel 1 was successfully completed, 40 days ahead of schedule. CCCC, a wholly-owned subsidiary of CCCC, and China's largest diameter shield machine exported overseas, independently developed by CCCC, played an important role in the project. "The total length of Ya'an Wanzhou High speed Railway is 142.3 km, of which Tunnel 1 is 1885 m long and the maximum buried depth is 26 meters. It is the 'throat' project of Ya'an Wanzhou High speed Railway Project." Lu Xiaomin, the former project manager of CCCC Tianhe Yawan Project Department, introduced that the most difficult problem during construction was that the tunnel construction conditions were extremely complex, and there was no relevant experience to learn from. He recalled that the geology of Ya'an Wanzhou High speed Railway Tunnel 1 is mainly composed of cohesive soil, mountain ash cemented round gravel, sandy soil and fine gravel soil. The groundwater level is high, the surface water is rich, and the tunnel body passes through volcanic deposits. The rock mass is broken and the self stability is poor. The tunnel also underpasses the structure intensive area, expressway and its interchange ramp, and sidepasses two buildings. The construction conditions are extremely complex, and the construction difficulty and risk are extremely high. Faced with such a complex construction environment, the constructors faced difficulties. CCCC Tianhe has designed a slurry balanced shield machine with a cutter head diameter of 13.19m, a length of about 101m and a weight of more than 2600 tons, and adopted the unique ultra long distance tool free technology and the appropriate cutter head anti mud cake design, the slurry system layered backwashing technology, the intelligent anti settlement control technology, the automatic control of the slurry circulation system and other world advanced technologies and pioneering technologies at that time. The shield machine is like a giant dragon passing through the underground, which is crucial to the smooth passage of the tunnel. During shield tunneling, the main slurry outlet and gravel box are frequently blocked, causing pressure in the pressure retaining system