China is about to build the world's longest trans-sea railway tunnel

Tunnel of cross-strait railway connecting mainland China with Taiwan will set the world's longest record if completed in 2030.

Chinese scientists are close to agreeing on the world's longest rail tunnel design linking the mainland to Taiwan after years of controversy, South China Morning Post reported yesterday. If the project becomes a reality, shuttle trains can glide through a 135km long tunnel at 250km / h in 2030. This ambitious project will include a startup project worth hundreds of millions of dollars. , according to scientists' plans submitted to the Chinese government.

According to many analysts, if China's science, technology and construction corporations can overcome the technical challenges of the project, this will be extraordinary success. " The project is among the largest and most challenging civil works in the 21st century , " said an unnamed scientist.

Tunnel design was completed last year with funding from the Chinese Academy of Engineering, the central government's largest advisory body for infrastructure construction. This design is increasingly receiving support from the research community and the tunneling industry. The idea of ​​a mainland link with Taiwan was proposed nearly a century ago and emerged in 2016 when the Chinese government put the high-speed rail network across the strait into the 5-year plan.

Picture 1 of China is about to build the world's longest trans-sea railway tunnel
The world's longest railway tunnel in China will connect the mainland to Taiwan.(Photo: Chron.com).

In the latest plan, the tunnel will be several kilometers longer than the 2016 proposal. The project will start from Binh Dam District, a trial free trade area set up by China in Fujian Province in 2013 to promote trade with Taiwan. Then, the tunnel will penetrate almost 200 meters, through complex layers of rock, including extremely solid granite, slipping through at least two major earthquake fault lines and returning to the ground in Hsinchu, Coastal city near Taipei.

The tunnel connecting to Taiwan will be 3.5 times longer than the world's longest undersea railway tunnel, the Channel Channel between England and France. The Manche Strait tunnel takes 6 years to build and spend 13.99 billion USD. When completed in 1994, the American Society of Civil Engineers likened the project to one of the seven wonders of the modern world.

The Chinese project has a similar layout to the Channel Channel, including a combination of three individual tunnels. Two main tunnels for trains run in opposite directions. A smaller service tunnel will contain power lines, communication cables and exits.

However, the Chinese project is different from the previous construction tunnels at the width of the main tunnel. These tunnels will be nearly a third larger than the Channel Channel. The wider design will allow ships to move faster and carry more bulky goods than the Manche Strait tunnel, which limits speed at 160km / h. One difficulty in the proposed plan is the possibility of constructing two artificial islands in the middle of the strait to place an air-handling station that takes clean air into the tunnel.

Researchers are working out of Binh Dam, conducting geological mapping, drilling soil and rock samples, running simulations on computers and analyzing potential environmental and project risks. large-scale tunnel crew. The survey of Fujian Geological Design and Geological Survey team was included in the $ 3.8 million feasibility assessment to build a road tunnel from Binh Dam to Phuc Thanh Town. in fujian. The survey team's findings will be submitted to the government next year.

The Binh Dam - Phuc Thanh tunnel worth $ 1.75 billion runs more than 11 km on the seabed, will pass Tokyo Bay Aqua Line to become the world's longest undersea road tunnel. Wide enough for three heavy cargo trucks to run side by side in each direction, the project would turn Binh Dam into a new hotspot for economic development in Southeast Asia, and pave the way for authorities to do so. Cross-strait tunnel projects are more challenging.

Zhu Hehua, head of the Department of Underground and Tunneling Research at Dong Te University, said that Binh Dam - Phuc Thanh Tunnel Tunnel would be a warm-up exercise for the construction of a railway tunnel from Binh Dam to Tan Truc, Taiwan. The shorter tunnel will be in the same area as the railway tunnel, requiring engineers to find ways to overcome similar geological and technical difficulties.

In addition to using tunneling machines such as the Channel Channel, China is considering using drilling methods and using explosives to build the Binh Dam - Phuc Thanh Tunnel at a lower cost and speeding up. If all three techniques are actually used to help save money and reduce construction time, this can be used to build a longer Binh Dam - Tan Truc tunnel. But scientists do not know the feasibility of using all three methods at the same time because of the complexity and unpredictability of deploying many techniques.