Features:

- Suitable for tunnel construction with high water pressure and high ground subsidence requirements; high efficiency, safe and reliable excavation;

- Two balanced modes of direct control and indirect control;

- Advanced and reliable cutterhead design and mud circulation system;

- Reliable main bearing, main drive seal and main drive reducer, long life and high safety factor;

- Independently developed control software system integration and key parameter matching technology, the machine performance is safe and reliable, and easy to operate.

Project Name: Beijing-Shenyang Passenger Dedicated Line

Project Overview: This project is the JSJJSG-12 tender section of the Beijing section of the Beijing-Shenyang Railway Passenger Dedicated Line. It is mainly the Wangjing Tunnel (long-length 8,000-meter-long, double-single-line tunnel, located between Beijing Dongwu and Dongliuhuan). , roughly along the Beijing-Chengde Expressway), this section of the contract to build DK22 + 710.7 ~ DK26 + 550 sections, of which 430m of open excavation construction section, 3168m of shield construction section, 210m of dark excavation construction section. A 3# shaft is set up at DK25+900 for the shield to start the well; a DK22+700 is equipped with a 2# shaft (constructed by the 13-segment) to receive the well.

This tender section is planned to be constructed by two mud-water balance shield machines. Each shield machine is driven into a single hole and tunneled from Shenyang to Beijing. The tunnel crossing stratum is mainly the Quaternary Holocene alluvial deposit (Q4al+pl) silt, silty clay, sand layer, clay layer and some clay layers.

Difficulties in engineering:

Large section and long distance excavation, shield tunnel excavation diameter is nearly φ11m, continuous excavation is up to 3168m, and equipment reliability is high;

The project environment is complex and the construction is difficult. Under the tunnel, the municipal roads such as Xiangjiang North Road and Shunbai Road, the Airport South Line Expressway, and the Maquanying Underground Station of Metro Line 15 are connected, and the underground pipelines along the line are more and dense;

The silt, silt and fine sand within 20m below the ground along the tunnel are seismic liquefaction layers, located at the top or middle of the shield tunnel, and are rich in micro-contained water, which is prone to water inrush, sand rushing, etc. Subside.

The environmental protection and water conservation civilization construction requirements are high. The bidding section is located between the East Five and East Sixth Ring Roads in Beijing, and there are many structures nearby.

Equipment overview: The mud balance shield machine model ZTS10820, the cutter head excavation diameter is 10870mm, the total length of the equipment is about 87m, the total weight is 1800t, and the installed power is 5300kW.

Innovations: 1. Large-diameter, long-distance continuous excavation; 2. Large-flow muddy water scouring circulation system; 3. High-efficiency material conveying system; 4. High-efficiency wear-resistant technology; 5. Fast-reducing technology; 6. Multi-point position on cutter head Scouring technology.

Schematic diagram of cross-section layout of shield tunnel section structure