A few days ago, the Malaysia East Rail project is under construction in full swing. It is a railway that carries the hopes of the Malaysian people. After the completion of the project, it will become the main traffic artery between the east and west coasts, open up the economic artery in the east and west direction of the Malay Peninsula, effectively promote the regional development of Malaysia, enhance the competitiveness of local industries, and greatly promote commerce, logistics, import and export and tourism, etc. The development of the industry improves the convenience of people's life.

The Yunding Tunnel constructed by China Communications Second Highway Bureau is a key control project for the entire line of the Malaysia East Rail Project. After the tunnel is completed, it will become the longest railway tunnel in Southeast Asia. Yunding Tunnel has a total length of 16.39 kilometers. It is a double-hole single-track tunnel. It adopts the same-direction excavation + drilling and blasting construction method. The construction technology is difficult, the environmental protection requirements are strict, the organization and coordination are difficult, and the social impact is extensive. The Yunding Tunnel is constructed with two open hard rock tunnel boring machines (TBM), with an excavation diameter of 8.98 meters, a weight of about 1,600 tons, and a length of 266 meters. It is the open hard rock tunnel with the largest diameter and longest excavation distance in Malaysia so far. boring machine.

The TBMs of Genting 1 and Genting 2 have a total length of more than 260 meters after assembly, and the weight of the whole machine is 1,600 tons. They are veritable giants. After the TBM equipment is manufactured in China, it is transported by sea to Port Klang, Malaysia, and then climbs over the mountains to reach the tunnel construction site. During the transportation process, many hardships were overcome. The section from the port to the construction site alone is 560 kilometers long, crossing the expressway many times, making organization and coordination difficult and safety risks high.

In order to ensure the safe delivery of equipment to the construction site, the project established a TBM transportation leading group, contacted professional transportation companies in Malaysia to hold several special meetings, discussed, deliberated and demonstrated the feasibility of the route plan, as well as transportation details and safety. After the transportation plan was approved by relevant departments in Malaysia, the first batch of oversized and overweight components of the Genting Tunnel TBM finally arrived at the construction site on July 12, 2021, kicking off the construction of the Genting Tunnel.

The surrounding rocks of the Yunding Tunnel are mainly granite, slate, and schist. There are 4 fault fracture zones and a 1.5-kilometer-long chlorite schist section. risk. To this end, the project team designed a follow-up emergency spray-mixing system, steel bar support mechanism, slag cleaning bucket + ring slag cleaner system, vacuum slag suction pump, strong drainage and emergency shelter, etc., in the guarantee While being safe, it improves the efficiency of poor geological treatment and reduces the impact of complex geological conditions on TBM construction.

At the same time, in view of the problem that the lubrication of the main drive cannot be observed and there is no oil in the cavity of the main drive, the project design reforms the way of lubrication supply and oil return, so that 5-6 barrels of lubricating oil can be stored in the main drive, and by increasing the external visible The oil level display can timely observe the remaining amount of lubricating oil inside the main drive, which greatly improves the lubrication effect of the main drive and reduces the probability of problems.

Due to the change of construction design of Yunding Tunnel, the two TBMs started in the same direction. Due to the limited space of the site, the project team designed the Genting No. 2 continuous belt conveyor as a three-stage slag transfer in view of the low efficiency of slag transfer, which rationally utilizes the limited space and improves the efficiency of slag transfer.

On November 1, 2021, the project team started the assembly of the first TBM, which was completed at the end of March 2022; on April 25, 2022, the project started the trial excavation of the first TBM, marking that the TBM has shifted from the preparatory stage to the construction stage ; On November 8, 2022, the TBM of Yunding No. 2 went into the tunnel for construction smoothly. So far, all the two TBMs have started to go into the tunnel for construction.

As of mid-April, the cumulative footage of Genting No. 1 Tunnel was 2,463 meters, and the cumulative footage of Genting No. 2 Tunnel was 2,390 meters. During the tunnel construction process, the project team carried out a number of scientific and technological innovations aimed at the key and difficult points of Yunding Tunnel construction, which further improved the tunnel construction efficiency.

According to the requirements of the Group's two monitoring centers, the project actively introduces TBM construction site supervision and remote monitoring systems, and builds and uses the Yunding Tunnel Multifunctional Exhibition Center. Through the visual monitoring in the tunnel and the timely transmission and transmission of TBM construction data, the safety and stability of construction and production are ensured, and domestic remote supervision and inspection are realized at the same time.

It is preliminarily determined to carry out a number of technical researches such as efficient construction technology of extra-long TBM tunnels, information-based construction management of extra-long TBM tunnels, etc., to solve the problems of TBM construction of long tunnels with unfavorable geological conditions, anti-collision of rail transportation equipment after TBM, synchronous lining construction of TBM, and tunnels in tropical rainforest areas. Design and construction energy saving and environmental protection and other technical problems.

Aiming at the TBM construction technology of unfavorable geological tunnels, the project carried out technical research work such as the treatment of unfavorable geological conditions such as tunnel fracture zones, soft strata, rockburst sections, and karst development sections, and technical research on reverse slope drainage of extra-long tunnels under TBM construction and improvement of horizontal transportation efficiency in the tunnel. Aiming at the TBM synchronous lining construction technology, carry out the design and research of synchronous lining trolley, reduce the interference between lining construction, TBM excavation and material transportation, and improve construction efficiency. Carry out research on energy-saving and environmental protection technology for tunnel design and construction in tropical rainforest areas, monitor tunnel construction environmental pollution, conduct in-depth research on environmental control technology, and realize standardized construction of green construction. Carry out research on the anti-collision system of rail transportation equipment after TBM. The TBM tunnel adopts four-track and two-track transportation. By introducing an information management system, vehicle collisions are reduced and locomotive safety is ensured. Aiming at the cost control of TBM tunnel construction, carry out overseas TBM construction organization research, give full play to the characteristics of TBM, safe and fast construction characteristics, optimize the allocation of overseas TBM resources, improve cost control, and summarize overseas TBM construction management experience. Editor / Xie Li