Wuhan sprints to build two subway lines within the year.
In the cross-river tunnel between popularization of science park station and danshuichi station of Wuhan Metro Line 12, the construction workers are working nervously on multiple faces. Photo courtesy of the correspondent.
At the depth of more than 30 meters at the bottom of the Yangtze River, the giant "earth tiger" is fully excavating; In Huashan, Wuhan, the subway line 19 tunnel has quietly crossed Yanxi Lake; In Wuchang South Area, the starting point adjustment project of Line 5 (Phase II of Line 5) is undergoing joint debugging and testing … … In the past few days, hundreds of work sites in Wuhan Metro have set off a great upsurge and made every effort to sprint the annual construction target. Jimu journalist learned from Wuhan Urban Construction Bureau that this year, the city plans to implement 13 subway projects with a total mileage of 182.8 kilometers, and build the second phase of Line 5 and Line 19.
Shield machine successfully crossed the Yangtze River levee.
At 9: 00 a.m. on June 3, the ring line of the subway in Asia’s largest city, Wuhan Metro Line 12, sent another good news — — In the river-crossing section from Popular Science Park Station to Danshuichi Station, the "Jiangcheng hms illustrious" shield machine successfully advanced to the 540th ring road, successfully breaking through 1080m, and safely realized two first-class risk sources, such as the shield machine originating and crossing the Yangtze River levee.
At the entrance of the construction site of the Popular Science Park Station, a row of cutters replaced by the shield machine are displayed, with an average diameter of about 45 cm and various shapes, which are like the "teeth" of the shield machine. When the shield machine digs underground, it relies on these teeth to "chew" obstacles such as rocks, mud and gravel to ensure the smooth progress of the shield machine.
"Don’t underestimate these knives, they are so small and worth 20,000 to 30,000 yuan." Ren Ruhua, project manager of China Railway 14th Bureau, the construction party, introduced that these cutters are divided into hobs, scrapers, tearing knives, etc. according to their different functions. They are installed on the cutter head of the shield machine in an orderly manner, and they cooperate with each other during construction to "gnaw" hard bones.
The shield machine has a diameter of 12.55 meters and a height of about 4 floors. There are 206 cutters installed on the cutter head at one time. "Because of the complicated geology, the cutters wear quickly. At present, we have replaced 350 cutters, which is equivalent to spending nearly 10 million yuan to replace 350 teeth for the shield machine." Ren Ruhua joked.
Jimu journalists enter the underground tunnel through the construction stairs. The tunnel that has been formed is very spectacular, and the tunnel segments are assembled neatly and seamlessly.
Zhou Xun, the owner’s representative of Wuhan Metro Group, said that segment construction is a very key link in subway construction, and its quality directly determines the safety of subway tunnels, and there should be no carelessness.
A segment weighs 13.5 tons. In the tunnel, a journalist saw a double-headed flatbed truck specially for transporting segments, which has a cockpit at both ends and can move forward and backward freely, which can solve the problem of vehicles turning around in the tunnel.
The section from Science Park Station to Danshuichi Station is about 4 kilometers long, which is the longest subway tunnel under construction in China. Line 12 is the first subway loop in Wuhan and the largest subway loop in Asia, with a total length of 59.9 kilometers and 37 stations. The line crosses the Yangtze River twice and the Han River once.
The "fastest" subway is scheduled to open to traffic this year.
"Now our interval tunneling task has been completed 98%, and victory is in sight!" On the morning of June 4th, Yin Huabin, project secretary of China Communications First Bureau, the construction party, said excitedly at Gujiashan Station, Bid 8 of Wuhan Metro Line 19.
The shield construction of this bid section is from Gujiashan Station to Wudong Station, with a total length of 3.2 kilometers, of which 1.1 kilometers goes under Yanxihu Section. In order to ensure the smooth crossing of Yanxi Lake, the most suitable shield machine was selected by repeated comparison before construction, and industry experts were invited to repeatedly demonstrate the construction plan and make detailed disclosure to the construction supervisors. During the shield machine crossing the lake, the builders used the remote monitoring system of the shield machine to carry out 24-hour uninterrupted monitoring. At the same time, they also used drones, telescopes and ships to patrol the water surface of Yanxi Lake every day. "We rented a small fishing boat to patrol the lake with drones, and found problems in time by checking whether the water body is bubbling or not, so as to start emergency plans and ensure that emergency rescue work can be carried out in time and effectively." Yin Huabin said.
In a clean and tidy tunnel, Zhou Hao, the second-level project manager of Wuhan Metro Group, said: "The tunnel segment damage, dislocation and water seepage have always been common quality problems in the process of shield tunneling. In order to effectively improve the engineering quality and create excellent projects, we strictly control the segment production from the source, and strive to create a pollution-free, dislocation-free, leakage-free and overrun-free ‘ Five tunnels ’ 。”
According to reports, Wuhan Metro Line 19 is designed to operate at a speed of 120 kilometers per hour, with a long-term operating condition of 140 kilometers, which is called the "fastest" subway line in Wuhan. It is expected to be opened for operation within this year, when residents in Guanggu area can go directly to Wuhan Railway Station through Line 19.
Steadily enter a world-class subway city
On the afternoon of June 4th, on the track of the starting point adjustment project of Wuhan Metro Line 5, the test train runs every 5 minutes and "gallops" back and forth between Hongxiacun Station and University of Traditional Chinese Medicine Station.
"This is an unmanned line, and it has to be docked with the first-phase site, so the debugging period of each system is several times that of ordinary lines." Yin Lei, the second-level project manager of Wuhan Metro Group, said that the joint debugging test is currently being carried out, and a systematic "physical examination" is carried out around the signal system, vehicle system, integrated monitoring system and communication system. During the joint debugging and test, the project team focused on the key parts, focusing on stations, yards, substations and other places, doing a good job in the investigation of potential safety hazards, maintenance and equipment operation, and strictly implementing various safety precautions.
In the joint debugging test, the smooth track has been affirmed by all parties. Zhou You, director of the Engineering Department of China Railway Shanghai Engineering Bureau, told the reporter that the starting point adjustment project of Line 5 benefited from the fact that they "grafted" the high-speed rail technology into the subway track laying, and controlled the track laying accuracy within 1 mm, which was much higher than the industry standard of 3 mm. "This will provide passengers with a more comfortable ride experience."
It is reported that since the opening of the first rail transit line in Wuhan in 2000, Wuhan rail transit has realized the historical transformation of "from scratch, from single line to network". At present, 11 lines have been opened and operated, with a total of 291 stations, steadily ranking among the top ten "metro cities" in the world. According to the relevant approval of the National Development and Reform Commission, by 2026, Wuhan will form a rail transit network with 14 subway lines and a total length of about 660 kilometers, and fully realize the "main city network and new city line".