China Railway Corporation successfully developed the first composite EPB shield machine in China-State-owned Assets Supervision and Administration Commission of the State Council.
On April 25th, the first composite EPB shield machine independently developed by the National "863" Plan was successfully rolled off the production line in the shield industrialization base of China Railway Tunnel Group in Xinxiang City, Henan Province, which marked a substantial breakthrough in the research and development of shield machines and the localization of their manufacturing in China, filled a gap in this field in China and set up a brand-new milestone in this field.
The CTE6390 composite shield machine has a diameter of 6.3 meters and a maximum driving speed of 8cm/min. It not only has strong geological applicability, but also has made remarkable progress in adapting to curve construction, steering rectification, rolling rectification and improving geological conditions. The design also fully considers the emergency treatment of shield construction when the cutter head is trapped, the safety protection when entering the cabin under pressure, and the response to emergencies such as water inrush, which has higher safety and reliability.
This shield adopts the operation mode of "independent design, independent research and development, and global procurement" and adheres to the design concept of "reliability, applicability, economy and advanced", realizing the leap from the key technology of shield to the whole machine manufacturing, realizing the digestion, absorption and re-innovation of foreign advanced technology, achieving the expected purpose in the aspects of localization rate of shield and cost reduction, and also making China’s shield manufacturing level enter the international advanced ranks. This success has opened up a more realistic and reliable channel for domestic tunnel and underground engineering to improve the construction speed, improve the safety and quality level, effectively control the cost and shorten the construction period, which will greatly promote the further popularization and application of shield machines in the domestic tunnel and underground engineering field, and will eventually end the history that China’s tunnel construction relies on foreign shields in complex geological environment.
China Railway Tunnel Group, a subsidiary of China Railway, undertook and successfully completed the development task of the shield machine. In recent years, relying on the engineering construction, the Group has found a correct position, actively undertaken the national "863" plan and the scientific and technological development planning project of the Ministry of Railways, attached great importance to the improvement of independent innovation ability, spared no effort in the research and development of shield machines, and made new achievements in TBM, shield machine assembly and debugging, cutter head manufacturing, hydraulic pressure, electronic control system and other aspects, thus giving birth to relatively sufficient research and development and manufacturing capabilities of shield machines and TBM. It took more than one year for CTE6390 composite shield machine to be successfully manufactured. It made full use of the construction platform of China Railway Tunnel Group, closely combined R&D with construction production, realized the strong combination of production, learning and research, and initially explored a shield machine manufacturing mode suitable for China’s national conditions, that is, taking the road of integration of design, manufacturing and construction.
Tunnel Group is the largest enterprise group in the field of tunnel and underground engineering in China, which integrates four functions: survey and design, building construction, scientific research and development and mechanical repair. At present, there are 50 professionals engaged in shield research and development, more than 400 people engaged in shield manufacturing, and more than 1,000 people engaged in shield construction. Shield machines have been used to successfully tunnel more than 100 kilometers, creating a precedent of crossing the Yangtze River three times and the Pearl River four times, and won three national scientific and technological progress awards in this field. At present, shield method is widely used in railway tunnels such as Shiziyang Tunnel in Guangzhou-Shenzhen-Hong Kong, Beijing Underground Diameter Line and subway sections in Xi ‘an, Guangzhou, Shenzhen and Shanghai. Rich experience in shield construction and numerous projects under construction provide the source of running water for shield research and development.