How to ＂leap＂ the world’s largest rectangular shield machine with three dimensions and functions？
The picture shows the world’s largest rectangular shield machine displayed at the achievement exhibition. Photo courtesy of China Railway Equipment
BEIJING, Beijing, Oct. 11 (Reporter Zhou Rui) Before 2008, China shield machine was still facing the situation that its key technology was monopolized by foreign countries. However, after the development of China Railway No.1, the first shield machine with independent intellectual property rights in China, China’s technological innovation in this field emerged in waves.
At the large-scale achievement exhibition celebrating the 70th anniversary of the founding of People’s Republic of China (PRC), the world’s largest rectangular shield machine developed by China Railway Equipment, a subsidiary of China Railway Industry, was successfully selected as one of the 150 "New China No.1" and exhibited in the "Towards Renaissance" exhibition area. Relevant persons were interviewed by Zhongxin. com to explain how the world’s largest rectangular shield machine was made.
Shield machine is the most advanced tunneling equipment in the world at present, and it is known as "the king of construction machinery".
The picture shows that in December 2013, the world’s largest rectangular shield machine rolled off the assembly line. Photo courtesy of China Railway Equipment
Before 2008, almost all shield machines used in domestic construction were imported, which was expensive and difficult to maintain. In April 2008, China Railway Equipment successfully developed the first composite EPB shield with independent intellectual property rights in China — — "China Railway No.1".
However, because the most common shield machines are all round, once the construction encounters a tunnel or subway entrance and exit in downtown area, it is inconvenient for the circular boring machine to display its fists and feet due to the thickness of the covering soil. In this case, China Railway Equipment put forward the idea of rectangular shield machine and began scientific research.
In December 2013, a rectangular shield machine with a length of 10.12 meters and a height of 7.27 meters was rolled off the production line of China Railway Equipment and used in Zhengzhou Zhongzhou Avenue Project, becoming the largest rectangular shield in the world at that time.
After achieving a major breakthrough from 0 to 1, the innovation of rectangular shield has not stopped. On the contrary, mastering the "innovation core" of rectangular shield has brought a wave effect to the subsequent technological innovation, and a series of new products and technologies have appeared one after another like waves.
First of all, it is a "triple jump" in product size.
After the "one jump" in Zhengzhou, in 2016, China Railway Equipment successfully developed a rectangular shield machine with a section length of 10.42 meters and a height of 7.57 meters, which was used in Tianjin Heiniucheng Road Crossing Project, setting a new world record for the largest rectangular shield in the world.
In 2019, the world record was refreshed again. At present, an oversize rectangular shield with a section size of 14.8m x 9.426m is being manufactured in Jiaxing.
Simultaneously with the "size increase", there is also a "three-in-one change" in the shape and function of the shield machine.
A shield machine with multiple cutters and hob. On May 26th, 2016, the world’s first rectangular shield pipe jacking machine independently developed by China was successfully rolled off the production line.
Combined shield machine with two transformers. On April 15th, 2017, the first test project of assembled underground parking lot constructed by shield method in China started tunneling under the square of China Railway Equipment Factory in Zhengzhou Economic Development Zone.
Three-variable horseshoe shield machine. Because of mastering the excavation technology of rectangular shield, the industrialization and branding of special-shaped shield machine in China Railway Industry is getting wider and wider. In addition to rectangular shield machine, horseshoe shield machine also appeared.
Regarding the significance of rectangular shield machine, the relevant person said that if the circular shield machine is a "big MAC" which is buried deep underground and suitable for long-distance tunneling, then the special-shaped shield machine is a "transformer" in soft soil. If the open-cut tunnel construction is compared to the surgery of "opening the belly", then the special-shaped tunneling technology is "minimally invasive surgery".
As a brand-new solution is provided for the construction of urban underpass tunnels, China rectangular shield machine has also begun to go abroad.
In October, 2015, the rectangular shield machine exported to Singapore rolled off the assembly line in Zhengzhou, creating a precedent for China’s rectangular shield machine to be exported overseas. In July 2019, the rectangular shield machine was once again exported overseas and successfully exported to Australia, which was applied to the connecting passage project of Melbourne West Gate Tunnel.