Breakthrough of Pearl River Shield Tunnel Project: Shield Tail Brush Guarantees Ultra-long-distance High-water-pressure Tunneling

Manufacturing factory:

Construction unit: Shield tail brush provides reliable protection for cable and equipment ends, helping block dust and debris while supporting clean, organized installations.

Shanghai Airport Link Line Large-Diameter Shield Tunnel Breakthrough in Soft Soil Strata, Shield Tail Brush Ensures Safe Long-Distance Shield Tunneling

Manufacturing factory:

Construction unit: Shield Tail Brush is designed for TBM sealing applications, providing reliable protection against slurry and water ingress. Its durable structure supports stable sealing performance during demanding tunnel construction.

Jinan Metro Line 4 Tunnel Breakthrough in Complex Water-Rich Sand Layer, Tail Seal Brush Ensures Safe Long-Distance Shield Tunneling

Manufacturing factory:

Construction unit: Tail seal brush is an essential sealing component used in tunnel boring machines to improve sealing performance during underground construction.

TBM Tail Sealing Brush Technology Supports Ultra-Large Diameter Shield Tunneling Projects with Reliable Sealing Performance

Manufacturing factory:

Construction unit: TBM tail sealing brush is a key component used in tunnel boring machines to provide effective sealing performance during underground construction.

High-Performance Shield Tail Brush Solves Complex Stratum Construction Problems — Case Study of Chongqing Rail Transit Line 27 Yangtze River Shield Tunnel Breakthrough

Manufacturing factory:

Construction unit: Shield sealing brush is a high-performance sealing component designed for tunnel boring machines, and durability to ensure safe and efficient underground construction operations.

Shield Tail Brush Technology Supports the Success of Cross-Sea Shield Tunneling Projects

Manufacturing factory:

Construction unit: Shield tail brush is a critical sealing component for tunnel boring machines, designed to prevent water, soil, and debris intrusion while providing excellent wear resistance, corrosion protection, and reliable performance during underground construction projects.

Shanghai Airport Link Shield Tunnel West Section Successfully Completed with Advanced TBM Tail Seal Brush Technology

Manufacturing factory:

Construction unit: The TBM tail seal brush provides excellent sealing performance, wear resistance, and durability to ensure safe and efficient tunneling operations in complex underground projects.

Guangzhou Nansha–Zhuhai Zhongshan Intercity Railway Shield Tunneling Section Completed

Manufacturing factory:

Construction unit: Shield tail brush provides durable seals, efficient cleaning and reliable protection for conveyor systems and equipment.

Steel Plate Tunnel Brush Improving Industrial Cleaning Efficiency and Conveyor System Maintenance Performance

Manufacturing factory:

Construction unit: steel plate tunnel brush delivers efficient cleaning and surface treatment performance with durable bristle structure and stable steel plate support ensuring thorough removal of debris and consistent industrial cleaning results

Advanced Shield Tail Sealing Technology Enhancing TBM Tunnel Construction Safety

Manufacturing factory:

Construction unit: Steel wire sealing brush provides effective sealing, wear resistance, and dust protection, ideal for tunneling and industrial equipment

Nepal Launches International Consultancy Tender for Kathmandu Valley Ring Railway Project

Manufacturing factory:

Construction unit: Steel wire sealing brush provides durable sealing, cleaning, and surface protection. High-strength steel wire bristles ensure long service life, efficient debris removal, and reliable performance for industrial applications

Chongtai Yangtze River Tunnel

Manufacturing factory:

Construction unit: The “Four World’s Firsts” have set a new global benchmark for high-speed railway tunnels. The tunnel boring machine (TBM) has successfully completed a single-heading tunnel crossing beneath the Yangtze River, spanning a distance of 11.3255 kilometers—the longest single-heading tunnel ever excavated worldwide. The tunnel utilizes the world’s largest-diameter high-speed railway TBM, the “Linghang,” with a maximum cutterhead diameter of 15.4 meters, creating an excavation cross-section of 186 square meters—equivalent to the height of a five-story building. The tunnel plunges as deep as 89 meters below the riverbed, enduring an ultra-high water pressure of 1.02 megapascals (equivalent to 10 atmospheres). This makes it the deepest and highest-pressure underwater tunnel in the Yangtze River basin. The project has also established a world record for high-speed railway tunnels in the 15-meter class, achieving a monthly advance rate of 718 meters—and averaging 600 meters per month. With its “strategic-level value” at its core, this project not only overcame world-class engineering challenges such as ultra-long single-heading tunneling, ultra-high water pressure, and complex geological conditions, but also achieved breakthroughs across the board in engineering technology, construction management, and ecological protection.

Zhuzhao High-Speed Railway, Jiangmen to Pearl River Delta Hub Airport Section, JJZQ-4 Contract, Guifengshan Tunnel Project

Manufacturing factory:

Construction unit: During construction, a record was set for the TBM’s daily advance of 21 meters and monthly advance of 395 meters in hard rock strata with an ultra-large diameter. Moreover, through industry-academia-research collaboration, the project successfully overcame the challenge of lacking prior experience in constructing ultra-large-diameter dual-mode shield tunnels, providing a benchmark for similar projects.

Zhuhai Tunnel Project

Manufacturing factory:

Construction unit: The construction environment is complex and the project’s difficulty ranks among the highest in China. According to the Zhuhai Municipal People’s Government: This project is an exceptionally challenging, ultra-large-diameter underwater shield tunnel project in China. The tunnel boring machine (TBM) must traverse a composite geological stratum that is soft above and hard below over a distance of more than 800 meters—a stretch that represents the longest bedrock section ever encountered in a Chinese underwater shield tunnel. At the same time, the TBM will pass very closely beneath numerous existing structures and must also go under two water supply pipelines serving Macao. The clearance between the top of the tunnel and the bottom of the pipelines is only 7.08 meters, making the construction highly risky.

Wen Yi Road (Zijin Port Interchange — Jingchang Avenue)

Manufacturing factory:

Construction unit: The 2,200-meter tunnel section using a shield machine needs to pass under several critical infrastructure facilities, including the Qiandao Lake water supply pipeline, the Hangzhou Ring Expressway, a high-pressure gas pipeline, and the subway express line tunnel. The northern tunnel runs within less than 10 meters horizontally from the airport express line and extends for a parallel distance of up to 1,200 meters. During construction, vibration and settlement isolation technologies were employed, ensuring that the settlement of the airport express line remained below 8 millimeters and thereby guaranteeing its safe operation.

Shanghai Rail Transit Metropolitan Line Airport Connecting Line Project

Manufacturing factory:

Construction unit: Leading smart construction technology: The “Jiyue” is equipped with ultra-large-diameter tunnel boring machine (TBM) synchronous jacking and segment assembly technology, enabling simultaneous excavation and segment installation—a “parallel” operation that reduces the average time per ring to just 85 minutes, boosting efficiency by nearly 30%. In Section 11, the “Hongpu” TBM has been deployed to implement an intelligent construction system for TBM tunnels, setting a new industry record for 14-meter-class TBMs with daily advances of 32 meters and monthly advances of 650 meters. Highly challenging construction risk management: The project area traverses central districts including Minhang, Xuhui, and Pudong, requiring the tunnel to pass beneath existing lines such as Metro Line 12 and numerous critical buildings and structures. For instance, in Section 3, Shaft No. 2 is located adjacent to the elevated section of the Shanghai-Kunming High-Speed Railway; during TBM reception, there was a risk of water and sand inflow, so the underwater reception method was ultimately adopted to mitigate this risk. In Section 13, the tunnel section passing under the Pudong Airport terminal building has a buried depth exceeding 50 meters—the deepest TBM tunnel section ever constructed in Shanghai—and requires long-distance tunneling through sandy layers.

Hangzhou Zhijiang Road Water Pipeline Tunnel and Road Improvement Project

Manufacturing factory:

Construction unit: The geological conditions are complex and construction is highly challenging: The tunnel needs to pass through a variety of intricate strata, including weathered quartz sandstone and silty clayey silt. The strength of the hard rock exceeds that of ordinary concrete by more than three times, causing extreme wear on cutting tools. At the same time, the tunnel successfully achieved a tight-radius curve with a radius of just 650 meters, overcoming the significant technical challenges associated with constructing ultra-large-diameter shield tunnels. Additionally, it effectively addressed the risk of uplift during shield tunneling in areas with extremely shallow overburden. The project features prominent green and立体 (three-dimensional) transportation characteristics: Upon completion, it will adopt a “four-lane双向 (two-way) road above ground plus four-lane双向 (two-way) road underground” configuration. The number of lanes on the ground-level roads will be reduced to widen the riverside scenic belt. In certain sections, sunken roads will be used to seamlessly connect parks with the Qiantang River. Meanwhile, the project integrates water pipeline corridors, simultaneously enhancing both the city’s water network and road network.

Shenzhen Chunfeng Tunnel

Manufacturing factory:

Construction unit: With an excavation diameter of 15.8 meters—equivalent to the height of a five-story building—it was the largest-diameter slurry shield tunneling machine in China at the time. The tunnel’s exceptionally long distance of 3,603 meters represents a rare project of its kind in China, and its construction difficulty ranks among the highest in the world. The construction area is located in the core district of Shenzhen, where old buildings are densely packed along the route. The tunnel directly passes beneath 28 existing old buildings and runs alongside 78 other structures, most of which have shallow foundations with poor resistance to settlement. Furthermore, the tunnel must pass through 11 fault fracture zones, with surrounding rock strength reaching as high as 173 megapascals. Additionally, the project involves continuous curves with small radii, while also needing to avoid sensitive areas such as subway lines and railway tracks—resulting in extremely high construction risks.

Shantou Bay Tunnel

Manufacturing factory:

Construction unit: It is the world’s first large-diameter shield tunnel located in an area with an earthquake intensity of 8 degrees. It is also Guangdong Province’s first highway tunnel constructed using the shield method beneath the sea, and has been dubbed “the most challenging large-diameter shield project” in China. At its deepest point, the tunnel lies 98.5 meters below sea level, situated in a region experiencing high seismic intensity of magnitude 8. To overcome challenges such as nearly 100-meter-high water pressure and severe chloride corrosion, the tunneling machine had to bore through extremely hard granite strata with a compressive strength of up to 200 megapascals. The shield tunnel section successfully passed through a 135-meter-long fault zone thanks to advanced ground consolidation measures applied ahead of the tunnel face. During construction, the team set several remarkable records: 14 meters per shift, 24 meters per day, and 432 meters per month—breaking the previous record for domestically produced ultra-large-diameter slurry balance shield machines.

Wuhan Yangtze River Road-Rail Tunnel

Manufacturing factory:

Construction unit: World’s First Public-Rail Integrated Construction Model: This is the world’s first completed shield-tunnel crossing a river that integrates both road and rail transportation. It features a dual-tube, three-layer structure: the upper layer serves as a highway smoke-exhaust duct; the middle layer accommodates a six-lane双向 highway; and the lower layer houses the tracks of Metro Line 7, a shared evacuation passage for both road and rail users, and utility tunnels—all designed to achieve intensive resource utilization. The construction faced enormous geological challenges: it was necessary to overcome the dual geological hurdles of the “diamond layer” and the “sticky rice cake” formation. The strata contain up to 70% quartz, resulting in extremely high hardness that led to the cumulative replacement of over 2,000 cutterheads during construction. At the same time, highly cohesive muddy siltstone posed another significant challenge, easily causing cutterhead clogging and mud cake buildup. To address this issue, the construction team adopted innovative methods such as injecting hydrogen peroxide. Abundant Awards and Technological Achievements: The project has won numerous prestigious awards, including the National High-Quality Engineering Award and the FIIDC Outstanding Engineering Award. Its research achievements were honored with the Second Prize of the National Science and Technology Progress Award. During construction, the team developed several technical procedures, such as the "Normal-Pressure Cutterhead Replacement Operating Procedures," and the newly developed "First Reverse, Then Forward, and Finally Expansion" reverse construction method significantly reduced construction costs.

Nanjing Dinghuaimen Yangtze River Tunnel

Manufacturing factory:

Construction unit: Leading in design scale: Adopting the world’s first double-layer, multi-outlet X-shaped overall design, this tunnel features a dual-tube, double-deck, eight-lane structure that efficiently diverts traffic flow. At the time, it was the largest project of its kind in the world. Extremely high construction difficulty: Dubbed a “world-class project located 70 meters beneath the riverbed,” it required crossing the Yangtze River’s embankment four times, with local overburden thickness as little as 9 meters. The tunnel had to pass through various geological strata, including soft soil and hard rock, with quartz content in the rock layers reaching as high as 65%. During construction, the water pressure reached up to 0.72 megapascals, and there were instances when only 3–4 meters could be excavated in a single day. Independent technological innovation: The tunnel boring machines used in this project boasted numerous pioneering technologies both internationally and domestically—for example, retractable cutterheads and a cutter disc capable of extending by 100 millimeters. These innovations enabled the machine to achieve an unprecedented record of continuous excavation for 2,580 meters in sandy gravel strata without changing cutters. The related technologies have earned multiple invention patents.

Singapore MRT Cross Island Line Phase 1 CR105 Project Tunnel

Manufacturing factory:

Construction unit: A benchmark for technological breakthroughs in Singapore’s metro sector: This is the first metro construction project undertaken by Singapore’s Land Transport Authority to employ a large-diameter tunnel boring machine, marking a departure from traditional metro tunneling methods locally. The geological and environmental challenges during construction are exceptionally high: the tunnel must pass through a variety of complex geological formations, including marine clay, mixed granite, and old impact sand layers, with highly variable geological conditions. At the same time, the tunnel needs to run beneath Changi Airport—a major international transportation hub—as well as other critical structures, placing extremely high demands on construction settlement control and equipment stability. Throughout the construction process, it is imperative to strictly avoid any adverse impacts on nearby key facilities.

Expansion of the Northern Section of the Western Passage (North-South Line) Project for the Hangzhou-Jiaxing-Huzhou South Drainage System.

Manufacturing factory:

Construction unit: A benchmark project in China’s deep tunnel drainage sector: As the country’s first-ever deep-tunnel drainage project, the northern section is one of the largest and most technically challenging segments in China’s drainage engineering field. The tunnel is buried 55 meters underground, requiring breakthroughs in several industry “bottleneck” challenges, including the construction of ultra-deep excavation support systems and the design of deeply buried tunnel lining structures. The construction environment and technical requirements are exceptionally stringent: the tunnel passes through ecologically sensitive areas such as the third phase of Xixi Wetland, placing extremely high demands on controlling construction-induced disturbances. To meet these challenges, the construction team employed technologies such as three-dimensional modeling for pre-construction simulations and ground-bearing capacity reinforcement. This enabled them to achieve millimeter-level precision in installing the core components of the tunnel boring machine. At the same time, a digital smart management platform was leveraged to monitor construction activities around the clock, ensuring both construction quality and ecological safety. With an ecological water allocation capacity exceeding 25 cubic meters per second, this project will effectively improve the aquatic ecosystem of the river network in the western part of the city.

Shenjiang Railway Zhujiang Estuary Tunnel

Manufacturing factory:

Construction unit: The hydrogeological challenges are of world-class magnitude. The tunnel has to pass through 13 different geological strata and 17 fault zones, with a solid rock section spanning an impressive 2.75 kilometers. The granite exhibits a compressive strength as high as 124.6 megapascals, and 22% of the tunnel’s length consists of alternating soft and hard strata. Meanwhile, the maximum water pressure reaches 1.06 megapascals—equivalent to 10.6 kilograms of pressure exerted on the tip of a fingernail. The tunnel’s maximum underwater burial depth is 115 meters, setting a new record for the deepest undersea railway tunnel in China. The tunnel’s geological conditions are exceptionally complex, with highly variable and intricate rock types, posing enormous challenges to both equipment performance and construction techniques. It presents three globally challenging issues: long tunnel lengths, ultra-high water pressures, and extremely complex geology.

Northern Section of the Wuhan Metro Line 12 PPP Project

Manufacturing factory:

Construction unit: Crossing Multiple High-Risk and Sensitive Areas: The northern section requires two crossings of the Yangtze River and one crossing of the Han River. The maximum burial depth of the tunnel roof beneath the riverbed reaches 51.7 meters below the bottom of the Yangtze River. Additionally, the tunnel must sequentially pass under the Wuhan Shipbuilding Vocational Technical College building, a dike, and the operating Line 1 light rail. The project must not only address tool wear caused by the riverbed rock formations but also ensure the safety of surrounding buildings and existing railway lines. Geological conditions are complex and highly variable: The construction section spans various geological strata, including silty clay layers and intricate rock formations at the riverbed. In some sections, the maximum burial depth for TBM tunneling reaches 41.2 meters. Particularly in areas directly beneath the Han River dike, precise control of excavation pressure is essential to prevent ground collapse or water inflow risks. Outstanding Connectivity and Interchangeability: As a key component of the ring line, the northern section connects multiple administrative districts, including Qiaokou and Jianghan. Via Hankou Railway Station, it provides interchange connections with more than ten metro lines. Moreover, the project includes the construction of the Danshuichi Vehicle Depot and the Fuxingcun Parking Lot. Upon completion, this project will help Wuhan achieve a transportation network featuring “three districts integrated into a single ring.”

Huzhou Nanxun Tunnel

Manufacturing factory:

Construction unit: Multiple sensitive areas to be traversed with stringent protection requirements: The tunnel boring machine (TBM) needs to sequentially pass beneath National Highway 318, the Changhu-Shen Class III waterway, the historic Qitang Canal Heritage Area, and the World Cultural Heritage Site of Nanxun Ancient Town. During construction, settlement and vibration must be strictly controlled. At the same time, leveraging the “Quan Zhiyun” intelligent monitoring and early-warning system, real-time monitoring of both the tunnel structure and its surrounding environment will be conducted to ensure the safety of cultural relics and scenic-area buildings. Significant geological and construction technical challenges: The tunnel passes through predominantly silty clay, silty clayey soils, and粉土 layers, with overburden thickness ranging from only 6.2 to 17.9 meters. This presents technical difficulties such as launching and receiving in extremely shallow overburden conditions and tunneling along tight-radius curves. The project employs an 11.7-meter-diameter slurry shield TBM, which addresses the stability issues associated with long-distance tunneling in soft ground by dynamically adjusting excavation parameters and precisely calculating cutterhead pressure.

Section 3, South Line of the Hangzhou North Ring Road - Tianmushan Road Improvement and Renovation Project

Manufacturing factory:

Construction unit: High difficulty in geological adaptation to the surrounding environment: The southern route is located in the central urban area and passes through a mixed geological formation comprising soft, silty soil and portions of hard rock. At the same time, it runs in close proximity to dense urban buildings. During construction, it must also be coordinated with the renovation of the Zhonghe Elevated Ring-North Interchange and the reconstruction and restoration of non-motorized vehicle bridges—tasks that place extremely high demands on construction accuracy and the protection of nearby facilities. Significant pressure from pipeline and traffic coordination: The section includes the construction of a 174-meter-long parallel ramp on the south side, and the surrounding area is densely packed with underground pipelines. During construction, it is necessary to simultaneously coordinate pipeline relocation and traffic diversion. This requires not only avoiding multiple power, communication, and other pipelines but also minimizing disruptions to the flow of traffic on major thoroughfares such as Tianmu Mountain Road and North Ring City Road, making traffic management particularly challenging.

Section 2, North Line of the Hangzhou Ring City North Road - Tianmushan Road Improvement and Renovation Project

Manufacturing factory:

Construction unit: High Construction Risks in the Core Urban Area: The project section is located in the Wulin Square commercial district, where buildings are densely packed and underground utility lines are intricately intertwined. The project involves relocating 13 power circuits of 35 kV and above, as well as 55 circuits of 10 kV. Additionally, the construction requires passing beneath multiple infrastructure elements, including Metro Line 2, Metro Line 10, and the Guxin River. In total, the project faces dozens of high-risk construction sites, making it extremely challenging to control ground settlement. High Equipment and Construction Difficulties: The transportation, assembly, and installation of the ultra-large tunnel boring machine—measuring 13.46 meters in diameter—pose significant challenges. The equipment bridge alone is 23 meters long and weighs 68 tons. Meanwhile, the project has required coordinating numerous traffic diversions, totaling more than 30 such diversions. During construction, it was essential to minimize disruptions to traffic flow in the city center. Highly Adaptable Construction Method: To address the complex and variable geological conditions along the route, the project innovatively adopted a slurry balance tunneling method. This method enables precise control over ground disturbance during excavation and, combined with advanced construction technologies, achieves an average daily advance rate of 4 meters, ensuring both construction progress and the safety of nearby facilities.

Pearl River Delta Intercity Railway Pazhou Branch Line

Manufacturing factory:

Construction unit: High construction difficulty: The section between Pazhou Station and Beigang Shaft represents the first project in China to use a 13-meter-class large shield tunneling machine for tunneling through a complex geological formation with an extremely small curve radius of just 500 meters. At the same time, it achieved the world’s first successful reception of a 13-meter-class large shield tunneling machine using a steel casing, setting a new industry record for the reception of ultra-large-diameter steel casings measuring 14 meters. High risk-control pressure: The core section requires passing sequentially beneath rivers, wetlands, operating subway lines, highways, and other critical structures, involving more than 30 crossings of various risk points in total. Moreover, the project is located in the central business district of Guangzhou, where buildings are densely packed and underground utility networks are highly complex, placing extremely stringent demands on controlling ground settlement and ensuring the safety of surrounding facilities.

Taiyuan Hub Loop Railway Tunnel

Manufacturing factory:

Construction unit: Strong technological innovation: This marks the first time in China that earth-pressure balanced tunnel boring machines have been applied to railway tunnel construction, breaking the limitations of traditional underground excavation methods for railway tunnels. The associated construction technology has been promoted across the entire national railway network by China State Railway Group, filling a significant gap in both research and application within the domestic field of large-diameter earth-pressure balanced tunnel boring machines. High geological and risk-control challenges: The tunneling route includes a 2,200-meter section characterized by a layer of coarse-grained pebbles with high content, where the largest pebble diameter exceeds 600 millimeters. At the same time, the tunnel must pass through 64 potential risk sources—including major urban thoroughfares, rivers, historic buildings, and residential structures—and the tunnel is buried at a depth of only 8 to 25 meters, placing extremely stringent demands on surface settlement control. Ultimately, the construction process managed to keep the maximum surface settlement within 10 millimeters.

Hangzhou North Ring Road Underground Passage

Manufacturing factory:

Construction unit: Record-breaking Construction of an Ultra-Shallow, Large-Diameter Shield Tunnel: This project marks Hangzhou’s first urban tunnel constructed using the large-diameter shield method. The cutterhead diameter of the shield machine employed in this project reaches 11.3 meters. Even more exceptional is that the shield’s launch point is just 3.4 meters above ground—a condition that ranks among the world’s rarest examples of ultra-shallow burial, placing extremely high demands on excavation accuracy and surface settlement control. Meanwhile, the tunnel’s maximum designed gradient reaches 5.5%, and the ground conditions at both the shield’s launching and receiving ends feature highly permeable strata with abundant groundwater, further complicating the construction techniques. Dense Crossing of Sensitive Structures: During construction, the tunnel must consecutively pass beneath several high-risk areas, including the Dong River, Tiesha River, the Shanghai-Hangzhou Railway, the Zhanlongkou Underpass, and the Bazi Bridge over the Dong River. High Coordination Challenges in Downtown Construction: The project route runs through numerous residential areas—including the Shuixingge Community and Zhanlongkou New Village—along with a dense network of underground pipelines. In addition to adopting phased construction methods and temporarily removing portions of the segregated pedestrian and bicycle green belts and bus stops, the construction team must also carefully manage the impact of construction noise and dust on nearby residents.

Hangzhou Metro and Phase III of Rail Transit Line 1

Manufacturing factory:

Construction unit: Hangzhou’s First Metro Tunnel Under the Qiantang River—Built as Hangzhou’s first large-diameter shield tunnel crossing the Qiantang River, and also the city’s first single-tunnel, double-track metro tunnel to span the river—this project has accumulated crucial experience for future metro tunnel projects that cross the Qiantang River in Hangzhou. With a large cross-section featuring an outer diameter of 11.3 meters and an inner diameter of 10.3 meters, the tunnel design breaks through conventional metro tunnel construction standards. The construction poses extremely high risks and challenges: the tunnel must pass beneath the Qiantang River, along with major embankments on both the north and south banks, oil pipelines, and the Xiaoshan Nanyang Oil Depot—several high-risk structures. The geological strata encompass a variety of complex formations, including silty clay, clay,粉砂 (silt), and gravel-bearing layers. Among these, the 800-meter-long “old clay” layer becomes significantly more viscous when exposed to water, greatly increasing excavation difficulty. Meanwhile, the tunnel’s lowest point is buried at a depth of 34.3 meters; this ultra-deep burial combined with high groundwater pressure makes the tunnel prone to issues such as face instability. Additionally, an innovative disaster prevention and evacuation technology combining lateral smoke extraction with longitudinal ventilation has been adopted, eliminating the need for an intermediate ventilation shaft in the middle of the river. This approach not only reduces costs but also minimizes construction risks.

Hangzhou Xiangji Temple Road West Extension Project

Manufacturing factory:

Construction unit: High ecological and cultural preservation requirements: The tunnel passes beneath the World Heritage site section of the Beijing-Hangzhou Grand Canal, with the historic Doudou Road district located upstream nearby. The area also features culturally protected buildings such as the ancient Xiangji Temple Pagoda. During construction, measures were taken—including excavating at a depth of about 10 meters below the riverbed and reinforcing the Xiangji Temple Pagoda with ground-based supports—to both preserve the scenic beauty of the canal and ensure the safety of the protected cultural heritage sites. The construction presents significant technical challenges: This project marks Hangzhou’s first-ever shield tunneling operation using a large-diameter machine with an exceptionally small curve radius. The tunnel’s minimum curve radius is just 500 meters—far lower than the standard 600-meter curve radius typically seen in 11-meter-class shield machines. Moreover, the project requires closely passing alongside multiple buildings and dealing with the complex conditions of twin-tunnel shield driving under the canal, placing extremely high demands on the control of tunneling parameters.

Zhoushan Lujiashi Submarine Tunnel

Manufacturing factory:

Construction unit: Geological construction risks are prominent: The tunnel boring machine (TBM) launch section has a minimum burial depth of only 6.2 meters, making it an ultra-shallow buried tunnel. The geological strata consist primarily of highly plastic, low-bearing capacity silty clay, which easily leads to issues such as TBM nose-down and uplift of tunnel segments. Additionally, the tunnel needs to pass beneath drainage boards and the Lujiashi seawall, crossing two areas where piles have been extracted. In the seawall section, PVC drainage boards penetrate the tunnel by 3 to 4.1 meters, posing a significant risk of entanglement with the cutterhead blades. This project is a benchmark transportation project within the province: it is Zhejiang Province’s first highway tunnel constructed using a shield tunneling method beneath the seabed.

Dalian Metro Line 5: Subway Tunnel Between Railway Station and Suoyuwan South Station

Manufacturing factory:

Construction unit: This project represents the world’s first large-diameter shield tunnel constructed in karst geology beneath the sea. The tunnel must traverse a 1,538-meter-long section characterized by highly developed karst features, where thousands of sinkholes of varying sizes are distributed, with the largest cavity reaching a height of 29.8 meters. At the same time, the tunnel must also contend with hard rock formations whose maximum compressive strength reaches 118 megapascals. Moreover, the tunnel faces a maximum hydrostatic head pressure of 0.5 megapascal—a high-pressure environment that poses significant challenges to the tunnel’s sealing and pressure-resistance capabilities. During shield tunneling, the tunnel will pass under several critical infrastructure facilities, including the Shugang Railway, Heizui Port, and Xianglu Reef Navigation Channel. Additionally, the surrounding area is marked by complex geological formations such as weathered zones and fault zones. It is essential not only to avoid any adverse impacts on these facilities during construction but also to address the difficulties in maintaining precise tunnel alignment caused by the uneven distribution of soft and hard strata.

Bo'ao Tunnel

Manufacturing factory:

Construction unit: Geological construction poses high risks due to the complex geological conditions in the construction area. The confined water head in the gravel layer at the bottom of the working shaft’s excavation pit fails to meet the requirements for resisting sudden water bursts. Along the route, chaotic and irregularly distributed boulders are found within the overlying silty and sandy strata, and numerous hidden ponds remain filled with uncleaned backfill. Moreover, the tunnel section contains self-contained biogas pockets; in certain localized areas, gas reservoirs with large gas volumes and high gas pressures may develop, posing multiple threats to construction safety. As a key project for transportation support during the Asian Games, the tunnel is located between the Qianjiang Third Bridge and the Qingchun Road Cross-River Tunnel, connecting two major new urban centers—Qianjiang New City and Qianjiang Century City. Upon completion, the tunnel will enable commuters to cross the river from the north bank to the south bank in just three minutes, significantly enhancing connectivity and efficiency between the two sides of the Qiantang River and providing crucial support for traffic management during the Asian Games.

Changde City Huanjiang River Crossing Tunnel (PPP Project)

Manufacturing factory:

Construction unit: The geological conditions pose significant construction challenges. In the tunnel section driven by shield machines, a full-face layer of gravel and pebbles stretches for as much as 3,000 meters. The largest gravel stones exhibit a compressive strength of up to 73 megapascals—exceeding the hardness of certain types of rock—and are highly abrasive, placing extremely high demands on both the cutter tools of the shield machine and the tunneling technology itself. As a benchmark for the localization of equipment technology, the “Yuan’an” is China’s first large-diameter, atmospheric-pressure, slurry-balanced shield machine capable of replacing cutterheads under normal pressure. It is a key project under the nation’s “863” Major Science and Technology Special Program and boasts completely independent intellectual property rights. Its successful application marks that China’s manufacturing of underwater shield tunneling machinery and construction technologies in complex geological conditions have reached world-class advanced levels. Moreover, it represents China Railway Construction Corporation’s first major livelihood project integrating surveying and design, equipment manufacturing, construction, and operational management into a single integrated undertaking.

New Zhengzhou Airport-Zhengzhou South Station Intercity Railway Tunnel

Manufacturing factory:

Construction unit: The project boasts numerous technological innovation highlights—it is China’s first intercity railway tunnel project featuring a dual-track, large-diameter shield tunnel. The tunneling machine has been equipped with a world-first six-axis underwater special-operation robot, which can effectively clean the cutterhead and solve the challenging problem of mud cake buildup. The tunnel passes through highly risky critical infrastructure, including a close proximity underpass beneath the central route of the South-to-North Water Diversion Project’s main canal. At this location, the tunnel arch is only 26 meters above the canal’s bottom, where the water pressure is 40 times higher than normal during tunneling. Moreover, the settlement must be kept within a strict limit of no more than 9 millimeters. To achieve this, the project team set up a pilot section and introduced advanced automated monitoring technologies, ultimately controlling the settlement in the underpass section to within 2.5 millimeters—a remarkable feat that ensured safe passage. The tunneling efficiency has reached unprecedented levels: the daily advance rate has been increased from an average of 3 rings per day to 7 rings per day, setting new national records for intercity railway tunnels, including a single-day advance of 22 meters, a monthly advance of 410 meters, and a one-time safe advance of 3,800 meters using large-diameter dual-track shield tunneling technology.

Beijing-Shenyang Wangjing High-Speed Rail Tunnel

Manufacturing factory:

Construction unit: The risk sources encountered during the tunneling process were exceptionally challenging. The tunnel continuously passed beneath the Airport Express, Metro Line 15’s Maquanying Station, 34 high-voltage 110-kV power transmission towers, and a residential area spanning 1.8 kilometers—each of these constituting Class-A risk sources. This project set a new national record for settlement control when large-diameter shield tunnels cross existing structures. By tackling environmental protection technologies that had long posed global challenges, the project successfully built one of the country’s first large-diameter slurry shield tunneling plants capable of achieving “zero pollution, zero leakage, and zero emissions” in slurry treatment, thereby completely resolving the issue of slurry contamination associated with urban shield tunneling construction.

Hengyang Second Ring Road Hejiangtou Xiangjiang Tunnel

Manufacturing factory:

Construction unit: The longitudinal gradient design presents a level of difficulty rarely seen nationwide. With a tunnel gradient reaching 5.0%, this is China’s largest “V-shaped” longitudinal-gradient, large-section slurry shield tunnel crossing the river. Such an extreme gradient poses extraordinarily high technical challenges for shield launching, and makes it particularly difficult to adjust the shield’s attitude during tunneling—especially during the “upward” driving phase, where precise parameter control is crucial. The geological conditions are exceptionally complex: the tunnel is located at the confluence of three major rivers—the Xiangjiang, Leishui, and Zhengshui—and must pass through unfavorable geological formations including karst regions, fractured zones, and strata that are soft on top and hard below. Moreover, the tunnel faces the challenge of groundwater corrosiveness. Additionally, the launch shaft is situated close to the eastern embankment of the Xiangjiang River, raising the risk of river water seeping into the excavation pit and compromising structural stability. The core technologies employed here are internationally leading; notably, the innovative use of silane impregnation technology for corrosion protection of tunnel segments—a technique commonly used in port engineering—is being applied for the first time to underground tunnel corrosion protection. Furthermore, the newly developed “grouting and compaction method for replacing low-density fill materials in riverbed cavities” has also reached an internationally advanced level.

Foguan Intercity New Shiziyang Tunnel

Manufacturing factory:

Construction unit: This tunnel was once the world’s largest-diameter underwater railway tunnel. It features a single-bore, double-track design, with a shield tunneling machine advancing alone for a total distance of 4.9 kilometers. During construction, the project encountered maximum water pressures as high as 0.9 megapascals and had to pass through three fractured zones and three sections of high-strength, full-face hard rock. Sections of full-face hard rock accounted for 48.5% of the tunnel’s total length, with the rock exhibiting a maximum saturated compressive strength of up to 75.7 megapascals. In response to this complex and varied geological environment, the construction team developed an efficient construction methodology, achieving a record-breaking monthly advance rate of 304 meters. The construction progress in the composite geological formations reached as much as 180 meters per month, with an average progress rate of approximately 126 meters per month—far exceeding typical tunneling speeds under similar complex conditions. This tunnel has truly become a high-standard, high-risk underwater railway tunnel for intercity rail transit.

Dongjin Tunnel

Manufacturing factory:

Construction unit: This marks the first time in China that earth-pressure balanced tunnel boring machines have been applied to railway tunnel construction. It also fills a significant gap in the country’s development and application of large-diameter tunneling equipment, breaking the reliance on imported core technologies for large-diameter composite earth-pressure balanced tunnel boring machines. The tunnel traverses a variety of complex geological formations, including new loess, silty soil, sand layers, and high-grain-size gravel layers—among which the high-grain-size gravel layer stretches over 2,200 meters, with the largest gravel particles exceeding 600 millimeters in diameter. At the same time, the tunnel passes beneath 64 critical structures—including major urban thoroughfares, rivers, bridges, historic buildings, and residential buildings—posing extreme challenges in terms of settlement control and construction safety. During the project, the tunnel boring machine achieved remarkable milestones: monthly advance rates of 420 meters and daily advance rates of 22 meters, while maintaining maximum surface settlement within 10 millimeters.

Baiteng Tunnel on the Menghua Railway

Manufacturing factory:

Construction unit: The world’s first horseshoe-shaped shield tunneling method was employed in this project. The tunnel is located on the fringe of the Maowusu Desert and primarily traverses loose geological formations such as sandy new loess and silt. The surrounding rock is mostly classified as Grade V and Grade VI, posing a high risk of collapse. Moreover, the tunnel must pass beneath critical infrastructure including the Baomao Expressway, natural gas pipelines, and high-voltage power towers—each presenting significant risks. As a result, the project faced exceptional geological and construction challenges. To address these unique difficulties associated with the unconventional shield design, an innovative approach was adopted: using a reinforced open-cut section to provide launching reaction force, thereby replacing the traditional reaction frame. Additionally, the tunnel segments were assembled using a “7+1” segmental configuration combined with an alternating odd-and-even ring jointing technique, ensuring structural stability. The “Menghua” shield machine set new records by achieving a maximum daily advance of 19.6 meters and a maximum monthly advance of 308 meters, completing the entire tunnel excavation in just 440 days.

Hangzhou Yanjiang Avenue – Canal and Jiang Tunnel

Manufacturing factory:

Construction unit: The first tunnel to cross the Hangzhou Canal fills a gap in local underground transportation along the canal. By eliminating the need to rely on bridges for crossing the canal, this tunnel effectively bypasses the peak-hour congestion in the Sanbao Ship Lock section of Hanghai Road, significantly improving traffic efficiency between Qianjiang New City and Xiasha. Located at the confluence of the Qiantang River and the Beijing-Hangzhou Grand Canal, the tunnel site features abundant groundwater and high hydrostatic pressure. To address the challenging safety issues posed by ultra-large and ultra-deep excavations under high-pressure water conditions, the construction team innovatively adopted the “top-down, reverse construction” method combined with an “island-style” excavation technique, successfully overcoming these formidable engineering challenges.

Changsha Nanhu Road Xiangjiang Tunnel

Manufacturing factory:

Construction unit: This project is the first tunnel construction in Hunan Province to employ the slurry balance shield method with a large diameter of 11.65 meters, breaking away from the traditional construction approach for cross-river tunnels in the region. Located in the heart of the city between the Orange Isle Bridge and the Monkey Stone Bridge, the project site features dense traffic and a complex network of underground utilities. The extremely shallow burial depth poses significant risks during tunneling; the construction not only requires extensive relocation of utility lines and demolition of buildings but also demands careful coordination between construction activities and urban traffic as well as residents' daily lives. Moreover, the site has numerous overlapping work areas and limited space. During tunneling, the team encountered a zone with developed karst caves, which became the primary obstacle to construction. To overcome this challenge, the contractor conducted pre-treatment of the caves by injecting grout beneath the riverbed and pre-casting concrete slurry to fill the cavities. At the same time, they adjusted tunneling parameters and slowed down the tunneling speed, successfully resolving this difficult issue.

Beijing-Tianjin Intercity Extension Project Section 3

Manufacturing factory:

Construction unit: The section of the project is located in a coastal alluvial plain, where the geological strata are predominantly composed of clay, silty clay, and silty loam. These soil types exhibit high sensitivity and low strength, with relatively high compression coefficients, making them highly susceptible to creep and disturbance. During tunnel boring machine (TBM) excavation, they can easily induce ground deformation, posing significant challenges to tunneling operations and the stability of surrounding rock masses. In this section, the upper layer contains Quaternary unconfined groundwater, while the underlying fine sand and silt layers harbor slightly pressurized groundwater. The tunnel runs directly beneath Jiefang Road’s commercial district, requiring continuous side or undercrossing of 32 commercial buildings. Along the route, eight locations have been identified as having extremely high risk levels, and five others as having high risk levels. Meanwhile, beneath the surface, there are 45 underground pipelines carrying electricity, water supply, gas, and other utilities; among these, 18 pipelines require special reinforcement measures. The minimum curve radius for the TBM tunnel is only 450 meters, accounting for nearly 25% of the total tunnel length. Furthermore, the project employs a large-diameter TBM with a diameter of 11.97 meters—a configuration that has no precedent yet in domestic tunnel construction projects using tunnels of similar diameters.

Tianjin Underground Diameter Railway Tunnel

Manufacturing factory:

Construction unit: The project is located in the core urban area of Tianjin and spans across three administrative districts. It crosses two major rivers—the Haihe River and the South Canal—and passes beneath several bridges, including the planned Metro Lines 4 and 6, as well as the Shizilin Bridge and the Jinguang Bridge. The tunnel’s maximum burial depth reaches approximately 43 meters. Remarkably, it successfully traversed large rivers and waterways under conditions of extremely shallow overburden—where the effective soil layer was less than 4 meters thick. For the first time in China, the BEAM system technology was employed for advanced geological exploration, enabling proactive identification and mitigation of geological risks. The slurry treatment system integrates a three-stage process that combines U.S.-designed hydrocyclone equipment with Spanish separation technology, achieving zero discharge of slurry waste and fully complying with environmental protection requirements. During tunnel boring machine (TBM) launching, a closed-type hard-interlocking pile reinforcement technique was adopted. Additionally, the project overcame significant technical challenges, such as extracting large-diameter bored piles in confined spaces.

Beijing Underground Diameter Railway Tunnel

Manufacturing factory:

Construction unit: The project is located in the core urban area of Beijing, where structures along the route are densely packed. The tunneling work requires close proximity to important cultural relics such as Zhengyang Gate and the Qianmen Arrow Tower. In sensitive areas, the settlement control standard is exceptionally stringent—no more than 3 millimeters—far lower than the 30-millimeter settlement limit typically applied in conventional shield tunneling projects. Meanwhile, the underground area along the route is crisscrossed with various pipelines, including water supply and gas lines. To address the complex geological conditions found in different sections of Beijing, we innovatively proposed the concept of “three-dimensional cutting.” We also achieved full domestic production of shield cutter tools, and our independently developed peripheral scrapers and tearing blades have been granted national utility model patents. Furthermore, we developed an automated technology for monitoring cutter wear, effectively solving the problem of rapid wear commonly encountered with imported cutter tools. By precisely controlling slurry pressure and air cushion pressure, combined with synchronous backfill grouting techniques, we have attained ultra-high-precision settlement control.

Lion Ocean Tunnel of the Guangzhou-Shenzhen-Hong Kong Express Rail Link

Manufacturing factory:

Construction unit: This is China’s first underwater railway tunnel constructed using shield tunneling technology. It marks the first time that large-diameter shield tunneling technology has been applied to the construction of a high-speed railway tunnel beneath water. Moreover, the project innovatively adopted a tunneling method known as “tunneling from opposite directions, underground docking, and in-tunnel dismantling,” setting a pioneering industry standard for precise underwater shield tunneling and in-tunnel dismantling. The tunneling operation was carried out beneath the main channel of the Shiziyang Strait, which is 3,300 meters wide and has a maximum water depth of 26.6 meters, facing a high hydrostatic pressure of 0.67 MPa. The geological strata traversed consist primarily of argillaceous siltstone and sandstone, interspersed with weak, "tofu-like" formations, numerous fault zones, and deeply weathered grooves. Additionally, the tunnel passes through sections with exceptionally shallow burial depths—where the tunnel crown is only 7 to 9 meters above the seabed—posing an extremely high risk of collapse. The project successfully overcame several globally challenging issues, including pressurized cutterhead replacement under water conditions. The comprehensive set of technologies developed during this project has been granted multiple patents and will subsequently be widely applied to more than 250 kilometers of composite-strata shield tunnels across China.

Hangzhou Qingchun Road Cross-River Tunnel

Manufacturing factory:

Construction unit: Among the standout technological innovation projects, a pioneering method—“Liquid Nitrogen Freezing In-Situ Repair of Shield Tunneling Machine Tail Brushes”—has been developed. This breakthrough addresses the persistent challenge of tail brush seal failure in high-pressure water-bearing strata, filling an international gap in this field. Additionally, a dynamic optimization system for shield tunneling construction parameters has been created, enabling real-time collection of 128 key construction parameters. Other innovations include advanced technologies for continuous treatment of high-pressure groundwater. These efforts have collectively resulted in cost savings exceeding 60 million yuan. The hydrogeological conditions are exceptionally complex, with significant variations in mechanical properties, which can easily lead to uneven stress distribution and subsidence of the tunneling machine. Moreover, the Qiantang River’s tidal influence is pronounced, with maximum tidal ranges reaching 5.6 meters and scour depths beneath the riverbed exceeding 7 meters, necessitating that the tunnel be buried as deep as 37 meters. The maximum water pressure reaches 0.47 MPa, and the presence of marsh gas within the strata further complicates the construction process.

Wuhan Yangtze River Highway Tunnel

Manufacturing factory:

Construction unit: The geological conditions are complex: the tunnel needs to pass beneath a riverbed at a depth of 57 meters, where the water pressure is high, and through highly permeable silty fine sand layers as well as unevenly hard and soft rock formations. Addressing technical challenges such as high water pressure, strong permeability, extremely shallow burial, long-distance tunneling, and precise attitude control, the tunnel boring machine (TBM) completed a single-pass excavation of approximately 2.5 kilometers beneath the riverbed, setting a new record at the time for China’s longest tunnel excavated by TBM under complex geological conditions characterized by high water pressure. This tunnel is also the first under-river highway tunnel in China constructed using a TBM with a diameter exceeding 10 meters that has been successfully started and completed. Moreover, it is the first tunnel in China to have been fully excavated through a continuous sandy stratum.

Wuhan Yangtze River Highway Tunnel

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Hangzhou Qingchun Road Cross-River Tunnel

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Beijing Underground Diameter Railway Tunnel

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Tianjin Underground Diameter Railway Tunnel

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Beijing-Tianjin Intercity Extension Project Section 3

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Changsha Nanhu Road Xiangjiang Tunnel

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Hangzhou Yanjiang Avenue – Canal and Jiang Tunnel

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Baiteng Tunnel on the Menghua Railway

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Fourth Bureau Group Co., Ltd.

Dongjin Tunnel

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Sixth Bureau Group Co., Ltd.

Hengyang Second Ring Road Hejiangtou Xiangjiang Tunnel

Manufacturing factory: NFM

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Beijing-Shenyang Wangjing High-Speed Rail Tunnel

Manufacturing factory: China Railway Equipment / China Railway Construction Heavy Industry

Construction unit: China Railway Tunnel Bureau Group Co., Ltd. China Railway Fourteenth Bureau Group Co., Ltd.

New Zhengzhou Airport-Zhengzhou South Station Intercity Railway Tunnel

Manufacturing factory: China Railway Construction Heavy Industry

Construction unit: China Railway 16th Bureau Group Co., Ltd.

Changde City Huanjiang River Crossing Tunnel (PPP Project)

Manufacturing factory: China Railway Construction Heavy Industry

Construction unit: China Railway Fourteenth Bureau Group Co., Ltd.

Bo'ao Tunnel

Manufacturing factory: China Railway Equipment

Construction unit: Hongrun Construction Group Co., Ltd.

Zhoushan Lujiashi Submarine Tunnel

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Hangzhou Xiangji Temple Road West Extension Project

Manufacturing factory: China Railway Equipment (NFM Modification)

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Hangzhou Metro and Phase III of Rail Transit Line 1

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Hangzhou North Ring Road Underground Passage

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Taiyuan Hub Loop Railway Tunnel

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Sixth Bureau Group Co., Ltd.

Pearl River Delta Intercity Railway Pazhou Branch Line

Manufacturing factory: Hairek

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Section 2, North Line of the Hangzhou Ring City North Road - Tianmushan Road Improvement and Renovation Project

Manufacturing factory:

Construction unit: China Railway Tunnel Bureau Group Co., Ltd.

Section 3, North Line of the Hangzhou Ring City North Road-Tianmushan Road Improvement and Renovation Project

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Seventh Bureau Group Co., Ltd.

Huzhou Nanxun Tunnel

Manufacturing factory: China Railway Equipment

Construction unit: Hongrun Construction Group Co., Ltd.

Northern Section of the Wuhan Metro Line 12 PPP Project

Manufacturing factory: China Railway Equipment

Construction unit: China Railway Tunnel Corporation

Expansion of the Northern Section of the Western Passage (North-South Line) Project for the Hangzhou-Jiaxing-Huzhou South Drainage System.

Manufacturing factory: China Railway Equipment

Construction unit:

Singapore MRT Cross Island Line Phase 1 CR105 Project Tunnel

Manufacturing factory: China Railway Equipment

Construction unit:

Wuhan Sanyang Road Yangtze River Tunnel

Manufacturing factory:

Construction unit: World’s First Public-Rail Integrated Construction Model: This is the world’s first completed shield-tunnel crossing a river that integrates both road and rail transportation. It features a dual-tube, three-layer structure: the upper layer serves as a highway smoke-exhaust duct; the middle layer accommodates a six-lane双向 highway; and the lower layer houses the tracks of Metro Line 7, a shared evacuation passage for both road and rail users, and utility tunnels—all designed to achieve intensive resource utilization. The construction faced enormous geological challenges: it was necessary to overcome the dual geological hurdles of the “diamond layer” and the “rice cake dough” formation. The rock strata contain up to 70% quartz, making them exceptionally hard—resulting in over 2,000 cutter changes during construction. At the same time, highly cohesive mudstone-siltstone formations posed significant risks of cutter clogging and mud cake buildup. To address these issues, the construction team employed innovative methods such as injecting hydrogen peroxide. The project has reaped numerous awards and technological achievements: it has won multiple prestigious honors, including the National High-Quality Engineering Award and the FIIDC Outstanding Engineering Award. Its research outcomes were recognized with the Second Prize of the National Science and Technology Progress Award. During construction, the team developed several technical procedures, including the "Normal-Pressure Cutter-Change Operating Procedures," and the newly devised "First Reverse, Then Forward, Finally Expansion" reverse construction method, which significantly reduced construction costs.

The Yongqing-Shanghai Section of the China-Russia East Pipeline Project – Yangtze River Tunneling Crossing工程

Manufacturing factory:

Construction unit: This project is the first-ever engineering undertaking in the national pipeline network construction. It features a single-heading tunneling operation using a shield machine over a distance of 10.26 kilometers, with 7,500 meters of underwater tunneling and a maximum ice pressure of 0.73 megapascals. Currently, it represents the longest tunneling distance, deepest burial depth, and highest water pressure among all existing oil and gas pipeline projects that utilize shield tunneling technology to cross rivers worldwide.

Global Finance | China-made tunnel boring machines set a new daily excavation record of 61.73 meters in Lesotho.

Manufacturing factory:

Construction unit: Xinhua Finance, Johannesburg, October 14 — According to reports from Maseru, recently, at the second phase of the Lesotho Highlands Water Project—the Polihali water conveyance tunnel project—the “Dayu Changfeng,” a tunnel boring machine independently developed by CCCC Tianhe, achieved a daily excavation rate of 61.73 meters, setting a new record for daily excavation performance among 5-meter-class dual-shield TBMs.

China Railway Equipment has developed the ultra-large-diameter tunnel boring machine “Barangaru.”

Manufacturing factory:

Construction unit: On July 30, as the cutterhead began to rotate slowly, the ultra-large-diameter tunnel boring machine “Balangaru,” developed by China Railway Equipment, was successfully rolled off the production line at the Zhengzhou National TBM Industrialization Center. This machine is a “sister” to the “Patigaran,” which rolled off the production line in April of this year, and together they will serve the Western Harbour Project in Sydney, Australia. Leaders including Zhuo Xingjian, General Manager of China Railway Equipment, and Jia Yaowei, Deputy General Manager, along with representatives from the contractor of the Western Harbour Project in Sydney, Australia, attended the roll-off ceremony.

China Railway Equipment’s first-ever export of a large-diameter tunnel boring machine to South America has been a resounding success!

Manufacturing factory:

Construction unit: Recently, good news came from Section 1 of the extension project for Metro Line 2 in São Paulo, Brazil: the large-diameter earth-pressure balanced tunnel boring machine “China Railway No. 1207,” developed by China Railway Equipment, has successfully completed the first-phase tunneling task of Section 1.

The “Funes” earth-pressure balanced dual-mode tunnel boring machine developed by China Railway Equipment.

Manufacturing factory:

Construction unit: On July 15, 2025, the “Funes,” a soil-pressure open-type dual-mode tunnel boring machine developed by China Railway Equipment, successfully started tunneling at the Fortezza railway tunnel project in Italy, marking the official entry of the project into the TBM construction phase.

The open-type TBM “Yunding No. 2” from CCCC Tianhe has successfully completed tunneling through Southeast Asia’s longest tunnel.

Manufacturing factory:

Construction unit: On July 12, the company’s open-type TBM “Yunding No. 2” successfully completed tunneling through the Yunding Tunnel—the longest tunnel in Southeast Asia—on Malaysia’s East Coast Rail Link. The company’s shield machines are accelerating their “going global” efforts, continuously providing high-quality, cutting-edge engineering equipment and full-industry-chain services to support global connectivity and contributing to the high-quality joint construction of the Belt and Road Initiative.

The “Qihang” dual-shield TBM has achieved a monthly advance of 701.8 meters on the Kaisaka Water Diversion Tunnel Project in the Philippines, setting a new record for tunneling progress!

Manufacturing factory:

Construction unit: Recently, we received news from the front lines of the Kaisaka Water Diversion Tunnel project in the Philippines! The “Qihang” dual-shield hard-rock TBM with an excavation diameter of 3.86 meters, developed by our company, achieved an impressive breakthrough of 701.8 meters in June, setting a new record for tunneling performance among small-diameter dual-shield TBMs of the same type.