Beijing Excavation! China's Largest Diameter Shield Machine

It is the largest diameter shield machine ' Canal ' designed and manufactured by Zhongjiaotian and independent research and development. The excavation diameter is 16.07 meters, the length is 145 meters, and the weight is 4500 tons.

The largest underground dragon in China was officially launched today in Beijing 's East Sixth Ring ( Beijing-Harbin Expressway-Luyuan North Avenue ) renovation project on August 10 to fulfill the major mission of Beijing 's urban sub-center construction.

The total length of Beijing East Sixth Ring Reconstruction Project is 16 kilometers. The shield tunnel section is about 7.4 kilometers long with separated double holes, and three lanes are arranged for each hole. The inner diameter of the tunnel is 14.1 meters and the outer diameter is 15.4 meters.

The Tunnel Bureau of the First Public Administration Group undertakes the excavation task of the shield tunnel section of the east line, starts the well on the north side of the old Beijing-Yuzhou Railway and receives the well on the south side of Tongsan Railway.

The starting point of the Beijing-Hangzhou Grand Canal that runs through the North-South economic exchanges is here. Now, how does the Canal show up here ?

Along the safety ladder, a bright mechanical world is displayed in front of the start-up well at the depth of 27 meters. The underground is illuminated by the light. In the long tunnel, the shield machine of Canal, 145 meters long, is “ steadily lying ” like a powerful drilling dragon.

This steel dragon adopts domestic independent technology and a number of domestic core components, which is like a train running underground. The head of the car is a shield, and the rear long carriage is called a trolley, including the main system and components. The front end of the shield machine is a circular cutter head with a diameter of 16.07 meters. The cutter head is equipped with hundreds of alloy blades, which can be described as ' armed to the teeth '. Excavation, rotation of the cutter head, and excavation of the front soil.

It 's easy to say, but to achieve drivage, in addition to a good ' tooth ' also need a smart ' brain ', that is, a sophisticated system support.

Canal is a slurry balance shield machine. Behind the huge cutterhead, there are slurry tanks, bubble tanks and human tanks. There are also five systems in the interior, namely, propulsion, grouting, assembly, slurry circulation and sealing.

There are two cabins behind the bubble cabin. When the staff enters the maintenance knife head of the bubble cabin, they need to pass through the cabin to gradually balance the pressure in the bubble cabin. Staff entering the bubble compartment works under pressure like divers.

For the first time, the "Canal" shield machine adopts the long-distance tunneling without tool change technology independently developed by CCCC Tianhe, and uses the large alloy tools unique to CCCC. The hierarchical tool layout design technology effectively increases the service life of the tool and greatly reduces the engineering risk.

Zhongjiaotianhe first applied optical fiber wear detection technology to shield cutter detection in the world. 12 replaceable wear monitoring cutters are designed to detect tool wear in real time, which is safer, more accurate and more efficient than traditional technology.

There is a cab in the middle of the fuselage, and the driver realizes the precise control of shield tunneling through intelligent management. The control room is only 4 square meters, with 7 display screens and dozens of buttons that can accommodate 3 to 4 people operating simultaneously. It can carry out more than 20 kinds of settings such as liquid transportation, excavation, pump operation, tool detection and slurry setting. The shield machine is tunneling according to the setting procedure, so the underground highway is constructed in tunneling.

First, the mud station starts screening, the shield operating room starts slurry circulation, and the cutterhead rotates, and the driving cylinder is started to ensure the normal tunneling parameters. At the same time, the segments are assembled in the rear part of the tunnel, and the segments, box culverts and other consumption materials are transported to the tunnel to prepare for the next tunneling.

The "Canal" steel dragon travels long distances underground, with 115 risk sources, 12 roads, 17 bridges, 4 railways, 3 rivers, 11 high-voltage towers, and 15 important pipelines. It can be described as underground. The dragon has passed through the ground, hiding behind the dangers and dangers.

Our "Canal" adopts automated monitoring technology, with a settlement control accuracy of 0.1 mm, layered backwashing technology to overcome the difficult problems of sudden strata stagnation, innovative application of two-fluid synchronous grouting technology, and comprehensively improve the quality of the formed tunnel.

A complete tunnel that we finally saw was formed behind the shield machine.

The project is expected to be completed by the end of 2023. After the completion of the East Sixth Ring Ground Improvement Project, there are 12 planned roads and 5 current roads in Beijing ' s urban sub-center to achieve east-west connectivity, alleviate traffic congestion in the East Sixth Ring Road, and integrate Tongzhou City with the administrative office area of the sub-center.

The original road pavement, slope, bridge, side ditch and other highway facilities of the East Sixth Ring Road were transformed into high-line park and transformed into a slow-moving system integrated with urban landscape. The greening area was increased by about 50 hectares to effectively improve the urban environment and become a good place for residents to walk and ride.