The Xikang High-Speed Railway is a rapid railway connecting Xi'an and Ankang, passing through Shaanxi Province and ultimately connecting to Chongqing. With a design speed of 350 kilometers per hour, this railway line features 26 large and medium-sized bridges and 20 tunnels, including 4 particularly long tunnels and 11 long tunnels. It could be described as a "tunnel road"! Construction of this railway officially commenced on June 29, 2021.

　　The Baiyangping Tunnel is part of the Xikang High-Speed Railway's Xunyang section, located within the jurisdiction of Tongmu Town, with a total length of 6606.43 meters. This tunnel is situated adjacent to the seismic fault zone of the mountain range, making the surrounding environment highly sensitive. Moreover, the geological rock formations along the route are not very favorable, with over 90% consisting of conglomerate rocks, and there are many sliding waves and dangerous rocks at high levels along the strata, posing significant safety risks during construction.

　　The LanHi LGM312C Intelligent Arch Anchor Integrated Trolley adopts an engineering chassis and is equipped with a single anchor rod system. The entire machine features functions such as four-wheel steering, four-wheel drive, and bidirectional driving. It operates with a dual diesel-electric power system, with electric operation and diesel emergency backup. With three-arm remote control, it meets the requirements for prefabricated arch installation, various step-by-step operations, and arch positioning adjustments. It can handle under-excavation and welding operations during arch installation, demonstrating strong adaptability to tunnel conditions.

　　As of the end of November 2023, excavation of the Baiyangping Tunnel has completed 65% of the entire tunnel length.

　　The high-speed Xinling Tunnel is located in Zhubu Town, Zhuji City, Zhejiang Province, 3.6 kilometers south of the Ciwu Exit. It is one of the important channels connecting the central and southern regions of Zhejiang Province with the city of Hangzhou, and also one of the tunnels with the highest traffic flow in Zhejiang Province. Due to the high volume of vehicles and frequent accidents, it often experiences congestion during holidays, earning it the nickname "King of Jams" on Zhejiang's highways.

　　The widening project of the Xinling Tunnel section starts at the junction of Zhuji and Xiaoshan, passing through the Ciwu Interchange and the Xinling Tunnel, and ends at the reserved position of the Hangzhou direction entrance and exit of the Zhubu Hub. The entire route is 13.636 kilometers long, with an investment of approximately 1.17 billion yuan, and is expected to be completed in 36 months. After widening, it will become an eight-lane bidirectional road with a design speed of 120 kilometers per hour. The width of the road section will reach 42 meters, the width of bridges will be 41.5 meters, and the newly built Xinling Tunnel section will have a roadbed width of 17 meters, adopting a three-lane cross-sectional form. After the widening project is completed, it will become the widest highway in the province.

　　The LanHi Intelligent Arch Spray Integrated Trolley is a tunnel initial support integrated trolley jointly developed by Blue Ocean Zhizhuang and Sichuan Road and Bridge Tunnel Branch. This equipment adopts an engineering chassis, four-wheel drive, four-wheel steering, and front and rear bidirectional driving structure. Its upper structure includes three arms with full sliding movement, three gripper hands, two baskets, two undercut hammers, and two anchor arm structures, enabling seamless connection of various construction processes during tunnel construction, improving construction efficiency, and reducing construction risks and occupational hazards.

　　It is understood that this construction project is only part of the standardization renovation project of the Xinling Tunnel. Next, there will be projects such as emergency telephone renovation, tunnel personnel induction system project, and demonstration tunnel construction project.

　　The Xiangli Expressway starts from Yisong Village in the southern part of Shangri-La City and extends all the way to the Baihanchang Interchange of the Dali Expressway, with a total length of 140.305 kilometers and a mainline length of 124.55 kilometers. This road is an important project supported by the state for the economic and social development of the Deqen Tibetan Autonomous Prefecture in Yunnan Province. It is also the first expressway in the Tibetan area of Yunnan Province and the highest-altitude expressway.

　　The Kaida Valley Tunnel is located in Yulong County, Lijiang City, with a total length of 3145.27 meters for the right line and 3145 meters for the left line. The deepest point is buried about 558 meters deep and crosses three fault zones. The exit of the tunnel is a typical area of large deformation of soft rock, and is severely affected by faults, with serious rock cracks, splitting, and deformation around the tunnel. During construction, facing the severe deformation of weak rock layers posed a huge challenge to the tunneling work.

　　The LanHi Intelligent Arch Spray Integrated Trolley is a tunnel construction equipment jointly developed by Blue Ocean Zhizhuang and Sichuan Road and Bridge Tunnel Branch. It adopts a structure with an engineering chassis, four-wheel drive, four-wheel steering, and front and rear bidirectional driving. The upper part is equipped with three arms with full sliding movement, three gripper hands, two baskets, two undercut hammers, and two anchor arm structures, which can achieve seamless connection of various construction processes during tunnel construction, improving construction efficiency and reducing safety hazards and occupational injuries.

　　On December 22, 2020, the left line of the Kaida Valley Tunnel on the Xiangli Expressway, with a total length of 3145 meters and crossing three fault zones, was successfully penetrated, laying a solid foundation for the construction of the entire expressway.

　　The Zijin Tunnel is part of the Dusishan Metro Project undertaken by China Railway Fifth Bureau, located between Yingxiu Town and Gengda Town in Wenchuan County, Sichuan Province. It is a single-hole double-track tunnel, construction of which began in October 2021, with a total length of 10.4 kilometers. The deepest part of the tunnel is buried 709 meters underground, making it a critical and important project along the entire railway line.

　　Since the Wenchuan earthquake in 2008, the rock in this tunnel section has developed cracks and faults, with some intrusion of small rocks in certain areas, and there is relatively little groundwater, which has increased the difficulty and safety risks of construction. Excavating in mountainous terrain, with the exit of the tunnel at a higher elevation, also presents challenges, as water flow during excavation can reverse, further complicating construction efforts.

　　The LanHi LGP340 intelligent arch anchor spray integrated trolley is a tunnel initial support integrated trolley jointly developed by Blue Ocean Zhizhuang and Sichuan Road and Bridge Tunnel Branch. The equipment adopts an engineering chassis, four-wheel drive, four-wheel steering, and front and rear bidirectional driving structure. The upper part is equipped with a three-arm fully sliding, three gripper hands, two baskets, two undercut hammers, and two anchor arm structures. The equipment can complete the entire tunnel initial support process without leaving the site, ensuring seamless connection of construction procedures inside the tunnel, greatly improving construction efficiency, and reducing construction hazards and occupational injuries.

　　Shizishan Tunnel is located in Binchuan County, Yunnan Province, with a total length of 29.42 kilometers, including five branch tunnels, and is part of the Dianzhong Water Diversion Project. This project faces numerous technical challenges, such as deep tunneling, groundwater treatment, crossing fault zones, and large deformations in soft rocks, bringing many risks and safety hazards.

　　The LanHi Intelligent Arch Anchor Spray Integrated Trolley is a tunnel initial support integrated trolley jointly developed by Blue Ocean Zhizhuang and Sichuan Road and Bridge Tunnel Branch. The equipment adopts an engineering chassis, four-wheel drive, four-wheel steering, and front and rear bidirectional driving structure. The upper part is equipped with a three-arm fully sliding, three gripper hands, two baskets, two undercut hammers, and two anchor arm structures. The equipment can complete the entire tunnel initial support process without leaving the site, ensuring seamless connection of construction procedures inside the tunnel, greatly improving construction efficiency, and reducing construction hazards and occupational injuries.

　　On August 22, 2022, the main tunnel excavation of Section 4 of Dali II in the Dianzhong Water Diversion Project, which was surveyed and designed by Yunnan Provincial Water Resources Design Institute, smoothly broke through the milestone of 20 kilometers in the Shizishan Tunnel.

　　The expressway from Leishan to Rongjiang is called Leirong Expressway. It starts from Leishan Interchange in the east of Leishan County, connecting to the completed expressway from Kaili to Leishan, passing through Datang, Taojiang, Yongle, Pingyong, and finally reaching Zhongcheng Interchange in the north of Rongjiang County, connecting to the expressway from Jianhe to Rongjiang, which is about to be completed. This road has a total length of 72.693 kilometers, with two lanes in each direction, with a speed limit of 80 kilometers per hour and a roadbed width of 24.5 meters. Leirong Expressway is part of the "678" expressway network in Guizhou Province. The entire project is expected to be completed in 36 months, with a total investment of approximately 12.297 billion yuan.

　　In the Guizhou Leirong Expressway project, the left bore of Baizhushan Tunnel has been excavated to a depth of 1,000 meters, marking another important progress after the right bore reached the same depth in December last year. Baizhushan Tunnel has a total length of 4,376 meters, making it the first ultra-long tunnel with both bores exceeding one kilometer along the entire line. In this tunnel, Section A3 of Leirong Expressway is responsible for the left bore, which is 2,188 meters long, and the right bore, which is 2,184 meters long, with a maximum depth of approximately 323 meters. Due to severe rock weathering, numerous joint fissures, low rock strength, and high water seepage, the construction difficulty has increased.

　　The LanHi  LGMP350D intelligent arch anchor spray integrated trolley is a tunnel initial support integrated equipment jointly developed by Blue Ocean Zhizhuang and Sichuan Road and Bridge Tunnel Branch. This equipment adopts a four-wheel-drive and four-wheel-steering engineering chassis, capable of bidirectional driving. Its upper structure adopts a three-arm fully sliding, three gripper hands, two baskets, two undercut hammers, and two anchor arm structures. This equipment can complete the entire tunnel initial support process without leaving the site, ensuring seamless connection of construction procedures inside the tunnel, greatly improving construction efficiency, and reducing construction risks and occupational hazards.

　　To ensure construction progress and safety, the project department repeatedly studied and formulated construction plans in the early stage of construction, ensuring the feasibility of the plans, and strictly followed the quality acceptance standards of high-speed railway tunnel engineering to ensure effective control of the quality of each procedure, laying a solid foundation for tunnel excavation and ensuring the smooth completion of various construction tasks.

　　The Chengkai Expressway connects Chengkou County and Kaizhou District in Chongqing City. It is a section of the national G69 Yinbai Expressway (from Yinchuan to Baise), with a total length of 129.3 kilometers. This road has many bridges and tunnels, accounting for 81% of the entire route, with a designed speed of 80 kilometers per hour and four lanes in both directions.

　　One particularly long tunnel on the Chengkai Expressway has a length of 11,489 meters for the left line and 11,456 meters for the right line. Ventilation, drainage, treatment of poor geological conditions, construction of inclined and vertical shafts, and measurement control are all key and difficult points during construction.

　　The Chengkai Tunnel passes through the Xuebaoshan National Nature Reserve, so a zero-excavation approach was adopted during construction to minimize damage to the original mountain. Previously, for aesthetic reasons, tunnel entrances would be built in a flat shape, requiring extensive excavation of the mountain, which could easily cause disturbances to the mountain and lead to geological disasters such as landslides at the tunnel entrance. However, the Chengkai Tunnel directly enters the mountain for excavation based on the terrain characteristics, better preserving the natural landscape of the mountain.

　　The LanHi Intelligent Arch Spray Integrated Trolley is a tunnel construction equipment jointly developed by Blue Ocean Zhizhuang and Sichuan Road and Bridge Tunnel Branch. It adopts a structure with an engineering chassis, four-wheel drive, four-wheel steering, and front and rear bidirectional driving. The upper part is equipped with three arms with full sliding movement, three gripper hands, two baskets, two undercut hammers, and two anchor arm structures, enabling seamless connection of various construction processes during tunnel construction, thereby improving construction efficiency and reducing safety hazards and occupational injuries.

　　The Chengkai Tunnel is the first highway tunnel project in the country to achieve fully mechanized assembly construction. Additionally, it adopts the most advanced domestic information management system and conducts comprehensive monitoring at the construction site. On March 31, 2022, the Chengkai Extra-Long Tunnel was fully penetrated, achieving an important milestone.

　　The Chongqing Rail Transit Line 18 North Extension Project is a subway line running from Xiaoshezi Station in the east to Fuhua Road Station (excluding) of Phase I of Line 18 in the west, with a total length of 10.61 kilometers. There are 8 underground stations along this line, providing convenient transfers to other 5 subway lines for passengers. Once operational, this line will further densify the subway transportation network in Yuzhong District, alleviate traffic congestion in areas like Hualongqiao, Daping, and Caiyuanba, facilitating travel for residents.

　　The LanHi LDJ400A-Ⅱ Multifunctional Tunneling Machine is specifically designed for non-explosive tunnel excavation. It primarily utilizes high-frequency hammers or breakers to impact and break rocks, or uses bucket teeth or rod wedges to crush rocks, while also leveraging the gravity below the surrounding rock to automatically break rocks. This machine can be operated locally or wirelessly controlled and is suitable for excavating tunnels with diameters ranging from 6 to 9.5 meters. It features functions such as high-frequency rock breaking, rapid excavation in soft soil, profile trimming, and spray dust removal, suitable for construction in areas where blasting is restricted, such as airports, residential areas, and wildlife reserves. This machine exhibits strong adaptability, capable of meeting the requirements of various types of surrounding rock construction, while also minimizing issues such as over-excavation, under-excavation, and collapse.

　　During the construction process, the Chongqing Transport Investment Rail Transit Group and the construction unit China Communications Construction Company actively addressed issues such as material transportation and equipment deployment. They conducted systematic analyses of the focus and difficulties of construction, formulated on-site construction plans, and clarified the work tasks for each stage to ensure the steady and efficient progress of the project construction.

　　The West Chongqing Railway has a total length of 739 kilometers, with the Wangjiatang Tunnel located in Guang'an City, Sichuan Province. This tunnel stretches for 2,317 meters and is constructed by China Railway Fifth Bureau. During the construction process, many difficulties were encountered, including toxic and harmful gases, water inflow, and soft soil geological issues. Additionally, it had to pass through water supply and gas pipelines, highways, high-voltage power lines, and residential areas. To protect the provincial cultural relics and local drinking water sources at the entrance of the tunnel, the engineering team designed a 292-meter adit to expedite the construction progress.

　　The LanHi Multifunctional Tunneling Machine is a specialized equipment used for non-explosive tunnel excavation. It primarily utilizes high-frequency hammers or breakers to impact and break rocks, bucket teeth or rod wedges to pry rocks in the surrounding rock, and leverage the gravity beneath the surrounding rock to automatically break rocks (high-frequency hammers mainly target rocks below 40MPa; harder and poorly developed rocks use breaker hammers for construction). It adopts local control and wireless remote control methods and can adapt to tunnel excavation ranging from 6 to 9.5 meters in diameter. It integrates functions such as high-frequency rock breaking, rapid excavation in soft soil, profile trimming, and dust suppression spraying, suitable for construction in areas where blasting is restricted (such as airports, residential areas, and wildlife reserves), exhibiting strong adaptability, and meeting various types of surrounding rock construction requirements while minimizing issues such as over-excavation, under-excavation, and collapse.

　　In early August 2023, the adit of the Wangjiatang Tunnel of the West Chongqing Railway was successfully connected. This signifies a new stage in the construction of the tunnel, with the additional excavation face accelerating the construction progress.

　　The S1 section of the Leshi Expressway is a new expressway, starting from Mabian and then connecting to the Renmu New Expressway's Mabian branch line, ending at Gudui Township in Leibo County, with a total length of 71.66 kilometers. This route passes through the Ma Bian East Wind Forest Farm. The S1-5 section of the Leshi Expressway in Gaozhuo Ying Township, Mabian Yi Autonomous County, Leshan City, is approximately 7.631 kilometers long, with 92% of the route consisting of bridges and tunnels. This section of the road has become an important part of the Leshi Expressway's entry into the uninhabited area for construction.

　　The Luoshanxi Tunnel of the Leshi Expressway is located in Gaozhuo Ying Township, Mabian Yi Autonomous County. It is a separated tunnel, with a single uphill direction throughout, with a gradient of 2.56%. The left line is 2,225 meters long, and the right line is 2,228 meters long. The net width of the tunnel is 10.75 meters, the net height is 7.15 meters, and the maximum burial depth reaches 311 meters. The main surrounding rocks are of grades IV and V. This tunnel is located on the southwest edge of the Sichuan Basin, connecting the transitional zone of the Yunnan-Guizhou Plateau, crossing very complex mountainous terrain and geological conditions.

　　The LanHi Multifunctional Tunneling Machine is a specialized equipment used for tunnel excavation. It primarily uses high-frequency hammers or breakers to break rocks, or utilizes bucket teeth or rod wedges to crush rocks, while also leveraging the gravity below the surrounding rock to automatically break rocks. This machine can be operated through local control or wireless remote control and is suitable for excavating tunnels with diameters ranging from 6 to 9.5 meters. It integrates functions such as high-frequency rock breaking, rapid excavation in soft soil, profile trimming, and spray dust removal, suitable for construction in areas where blasting is restricted, such as airports, residential areas, and wildlife reserves. This machine exhibits strong adaptability, capable of meeting various rock construction requirements while also minimizing issues such as over-excavation, under-excavation, and collapse.

　　During the project construction, the construction team overcame many difficulties, such as complex geological conditions, safety production, and ecological protection. They adopted the concept of "permanent convergence" and used the completed Xiaoliangshan Bridge as a construction platform to ensure the smooth construction of the Luoshanxi Tunnel of the Leshi Expressway. While ensuring safety and environmental protection requirements, they optimized the design of the Luoshanxi Bridge, reducing costs and shortening the construction period by 6 months. The project also introduced advanced technologies such as the tunnel information center control room and personnel positioning system, using equipment such as light-sensitive probes for comprehensive monitoring inside the tunnel to ensure construction safety. They also used wet spraying machinery instead of manual tunneling operations to effectively reduce risks, safeguard workers' health, and improve project quality. The project also actively practiced the concept of green expressway construction, avoiding damage to the original ecological vegetation caused by blasting construction by building tunnels and investing heavily in vegetation greening work.