Lead
The world's tallest EPB is not in the highlands of the mainland, but in Nepal's Kadima region, a 2,000-tonne TBM that is the height of a five-storey building.
This machine was originally intended to help Nepal build a second railway, called the Kadima Railway, but the tunnel of the Kadima Railway became the largest relic in Nepal's history after being excavated halfway through the severe geological conditions and the problem of manpower and mechanical force.
In the East, we now have the world's highest altitude plateau railway, that is, the China-Nepal Friendship Railway.
How will the world's heaviest EPB help China and Nepal break through the huge mountains of the Himalayas?
China's engineering capabilities.
China's engineering capabilities have always been recognized as the top in the world, especially in recent years, and its status in international construction has been on the rise.
In Nepal, China has helped Nepal complete the construction of a railway and a hydroelectric power station, and is also preparing to build a second railway, called the Kadima Railway, which is already halfway tunneled.
Records of various buildings are constantly being set around the world, the world's largest membrane stadium has been built in Qatar, and the world's largest airport is rushing to build new projects with China's engineering capabilities.
In the East, our country's engineering capabilities are also recognized as the strongest, from large dams to the Maritime Silk Road, Chinese projects can be found everywhere.
In the Qinghai-Tibet Plateau and the Sichuan-Tibet Plateau, China has set a new record for plateau architecture.
On the Qinghai-Tibet Plateau, there is the first bridge of the Qinghai-Tibet Plateau with an altitude of more than 5,400 meters, and on the Sichuan-Tibet Plateau, there is a giant bridge on the Sichuan-Tibet Plateau with an altitude of 5,300 meters.
The "China-Nepal Friendship Railway", which connects Qinghai and Tibet with South Asia, has built a new railway with an altitude of 5,180 meters.
The heaviest shield machine in the world.
However, the world's tallest EPB is not in the highlands of the mainland, but in Nepal's Kadima region, a 2,000-tonne, five-storey giant TBM.
Also nicknamed the "Elephant" by locals, the giant TBM was originally used to excavate tunnels for the Kadima Railway.
However, because the geology of the tunnel is so complicated, only 50% of the project is completed, and it has become a permanent monument in the world, and it is preserved as a stalactite cave.
It is the exquisite fossil of every meandering life, covered with the dust that belongs to humans.
This relic is the famous ruins of the Oiratna Railway, which is the largest relic in the history of Nepal, and as for why the Kadima Railway became a ruin, it starts with the steep excavation of the Kadima Railway.
We know that Kadima is located in Nepal.
Nepal is originally a mountainous area, and Kadima is a "mountain village" in the mountains, its geological environment is very harsh, this small village has to experience four seasons a year, but unlike the four seasons in other parts of the world, the four seasons of Kadima have to come with rain.
Every time the rain falls from the sky, the water in Kadima swells and the roads in the village become slippery.
This railway, called the Kadima Railway, is designed to solve this problem, and it is a small train that circulates the village of Kadima, thus solving the transportation problems of the villagers.
If the railway is built, it will be 34.50 kilometers long and will connect three railway stations.
The worst part of this railway is the tunnels, which are one-third of the length of the railway, which is a complex geological area.
In this dark tunnel, it is always a bleak scene, and the villagers often see wild beasts walking along the tracks, but this is not the point.
During the construction of the Kadima Railway, the biggest concern for engineers was the accumulation of water in the tunnels.
The geology of Kadima is already very unstable, and Kadima is a small village that is very affected by the rainy season.
This means that the most feared thing in Kadima's tunnel is stagnant water, and once water accumulates in the tunnel, the people inside are very likely to be trapped for a long time, or even lead to death.
The engineers were disturbed by the first tunnel construction, and the second time they entered the tunnel, they sealed both ends of the tunnel with a small window on the door, so that they were not afraid of water.
This fear of the tunnel greatly delayed the workers who traveled to and from the tunnel, resulting in a slow progress of the project.
The highest railway in the world.
However, there is another difficulty in the construction of the Kadima Railway, and that is Kadima itself, the terrain of Kadima is complex, not only with many mountains, but also with a lot of large and small rivers.
In the process of excavation, the engineers encountered a lot of rivers, but even outside the country, China has the world's most advanced shield machine, so the project is not too problematic.
In the Kadima Railway, we use a 2,000-tonne TBM, which is 11 meters in diameter.
However, even in China, such a shield machine is very rare, and it was developed and manufactured by China Railway Engineering Equipment Group, which was tailor-made for the Kadima Railway.
Its appearance has set a new peak in the history of mountain railway development, allowing everyone to see the strength of China's engineering.
The TBM was also named "King Kong".
There are a total of seven tunnels to be excavated in the Kadima Railway, the longest of which is called "Tunnel 74".
During the excavation of the tunnel, a 120-ton shield machine had just entered the tunnel when a serious accident occurred, and the shield machine suddenly stopped working.
After the staff checked, it was found that the shield machine was hit, but fortunately, there were no casualties in this impact.
Later investigation revealed that the impact was caused by the tearing off of the coating on the surface of the shield machine's fireproof board, which caused the smoke detector inside the machine to sound an alarm.
The staff working in the tunnel hurriedly evacuated, and the machine was knocked out of work, but the test results were still very successful, which shows that the shield machine still has very good fire and explosion prevention functions, which also greatly protects the safety of the tunnel, which is the greatness of Chinese engineering in the world.
epilogue
China can be said to be very experienced in helping Nepal build roads, and Nepal also has a lot of trust in China.
As long as the Chinese company brings China's shield machine, then they will definitely be able to see the Nepalese government judge grant them a letter of confidence, not only will not ban China's shield machine, but will also pave the way for it in the first time.