What equipment does the shield working shaft have?

Question 1: What equipment is in the working shaft of shield tunneling method? Shield tunneling construction tools affect traffic, weak layers are also highly adaptable, surface settlement is easy to control, construction noise and other advantages, and avoid pipelines on both sides of the road. The construction process of the disturbed shield tunnel is complex and has high construction precision and technical content. Its main construction steps are:

(1) Work shafts are built at the beginning and end of the shield construction tunnel, also known as the starting shaft and the arrival shaft ( (also known as assembly room, disassembly room);

(2) Assembly position in the shield end shaft;

(3) Reinforcement of the opening layer;

(4) Relying on the thrust of the shield jack (acting on the working shaft wall of the assembled lining ring), the shield is pushed at the starting working shaft wall hole (process shield hole);

(5) The shield layer is pushed along the design axis , promote the installation of lining segments with broken soil;

(6) and grouting into the back gap of the lining to prevent layer movement and fix the position of the lining ring;

(7) The shield enters the terminal work Well and dismantle (process shield boring into the hole), if construction needs, pass through the working well or shield station and then move forward

The shield excavation process is divided into 4 stages:

① Negative loop Sectional excavation (starting from the assembly of the pipe segments until the shield tail leaves the inner wall of the tunnel); ② Sectional excavation (the shield tail leaves the inner wall of the tunnel and ends when the shield tail is 40 m away from the inner wall of the tunnel);

③ Sectional excavation (the tunnel The excavation of the tunnel section ends at the end of the tunnel excavation section and the tunnel tunnel excavation begins);

④ Tunnel tunnel excavation (the shield incision is 5 times the shield diameter from the outer wall of the tunnel shaft, starting from when the shield tunnel enters the base)

Modern shield tunneling can be applied to various complex engineering and hydrological conditions, has fast construction speed, and has the advantages of energy efficiency to control surface settlement. Shield tunneling construction requires relatively long investment in the design and manufacture of shield tunneling and ancillary equipment, as well as the construction of end shafts, etc. Engineering facilities are highly dependent on the surrounding rock conditions for their construction technical details. It requires detailed hydrological survey work in advance, and various contingency preparations must be made according to the complexity of the surrounding rock. It is advisable to use open excavation or mines, and water development , the stability of the surrounding rock is poor, and the tunnel construction period is urgent, it is economical and reasonable to use shield tunnel construction

Question 2: What are the main equipment in the working shaft during shield tunnel construction? (1) Eccentric multi-axis shield method

(2) MF (Multi Face) shield method

(3) Free section shield method

( 4) Sphere shield method

(5) MSD (Mechanical Shield Docking) shield method

(6) MMST (Multi-Micro Shield Tunnel) shield method

(7) Bubble shield method

(8) Excavation surface chemical grouting balanced shield method

(9) Double circle (DOT) shield method

(10) H and V-shaped bifurcated shield method

(11) ECL (Extruded Concrete Lining) shield method

(12) Soil pressurization Shield tunneling method

(13) Locally expanded shield tunneling method

"Bridge shield tunneling method" is a relatively advanced roof culvert construction method that retains the traditional roof culvert construction method. On the basis of the roadside prefabrication technology of bridge and culvert structures, major reforms have been made to the structure jacking support method, and the open-cut trenching has been replaced by underground shield-excavation support. The advancement of underground excavation has reduced the impact of construction on traffic.

Question 3: What is a working well? Working wells are generally used for the construction of tunnels or subways in municipal projects, as well as for the construction of water supply and drainage projects, oil wells, and mine projects.

A working shaft is actually an underground passage for construction of tunnels or subways.

Due to different projects, working wells are also different and there are many types.

Pipe jacking in municipal engineering is used for tunnels or subways. The working shaft is where the shield goes down. The working area is ready for departure. The receiving shaft is where the shield comes out of the tunnel.

The working shaft of municipal pipe jacking construction is the jacking operation room. Jacking starts from the working shaft and comes out of the receiving shaft.

Masonry construction of water and drainage projects: There should be no open joints during the construction of the working well, the mortar should be full, the mortar joints should be smooth, the surface should be calendered, and there should be no hollows, cracks, etc. When constructing a rectangular inspection well, the well walls should be vertical to each other, the cover plate should be stable during the hoisting process, and personal safety during the hoisting process should be ensured. When the concrete or mortar of the working well reaches the design requirements, use sand and gravel to backfill within 40 meters from the well circumference. The backfilling should be strictly layered. The thickness of each layer should be controlled within the range of 20 meters. Use a tamping machine for light tamping to ensure The compaction meets the requirements. Pipe backfilling: When backfilling the trench, there must be no accumulated water or silt in the trench. When the pipeline is buried, the height of the top of the upper row pipe from the road surface shall not be less than 0.8m, and the height of the passing pipe shall not be less than 1m. After the pipe is installed, it shall be backfilled with sand and settled and compacted as required. Completion cleanup: After the project construction is completed, the site will be initially leveled and the manhole cover will be installed in time.

For example: in terms of working shafts for tunnels or subways, the Bund passage project is a key project in the comprehensive reconstruction of the Bund. The shield propulsion section runs from the Tiantong Road working shaft to the Fuzhou Road working shaft, with a total length of 1,098 meters. .

The project uses the super-large-diameter earth pressure balance shield machine "Bundan Tongtai" for construction. This is the first time in China that such a large-diameter earth pressure balance shield machine has been constructed. "New drivers" encountered complex road conditions as soon as they took to the road. The first major difficulty in the project is the construction of submerged soil. 1/3 of the entire line construction is for ultra-shallow soil construction. The distance from the ground to the top of the shield is about 8 meters, which is only 0.6 times the diameter of the shield. However, traditional construction requirements The covering soil must be at least equivalent to the diameter of the shield. It is conceivable that it is difficult to control the floating of the tunnel during construction. The second biggest difficulty is the complex surrounding environment.

"The Bund Tongtai" passes under the gap between the Bund Historical and Cultural Reserve and the Huangpu River. Along the way, it passes closely by the Pujiang Hotel, Waibaidu Bridge, the Bund International Architecture Expo Group, and the Nanjing East Road Underpass. , Beijing East Road underground passage and other buildings. According to statistics, there are 1 bridge, 4 tunnels and 18 protected buildings densely distributed along the route of more than 1,000 meters.

Question 4: What is a shield receiving shaft? It is a foundation pit or air shaft used for the launch of the shield machine.

Question 5: What is the shield shaft in the subway? The shaft that provides conditions for the shield machine to operate is called a shield shaft.

Question 6: What regulations should be complied with when constructing shield tunnels entering and exiting the working shaft? 1. When the soil layer is unstable, the soil at the entrance needs to be reinforced. Before the shield tunnel exits from the working shaft, the reinforced opening should be

2. Before removing the sealing door from the starting working shaft, the shield should be brought close to the Dong mouth. After removal, the shield should be quickly pushed into the soil layer to shorten the exposure of the front soil layer. time; a hole water-stop sealing device should be installed in time between the hole ring and the outer wall of the segment;

3. In the 50-V 100 ring after the shield exits the working well, the pipeline axis measurement and formation deformation should be strengthened Monitoring; and the excavation operation requirements in the next stage should be adjusted and optimized based on the construction parameters of the shield entering the soil layer;

4. The front soil pressure should be reduced when entering the receiving working well, and the sealing door should be removed when Stop the advancement to ensure the safe removal of the sealing door; after the sealing door is removed, the shield should be advanced and assembled as soon as possible to shorten the time of entering the receiving working well; after the shield reaches the receiving working well, the hole circle gap should be closed in time;

5. The axis and the center position of the tunnel door should be measured 100 rings before the shield enters the receiving working shaft, and the shield's propulsion posture and direction should be adjusted in a timely manner according to the measurement conditions.

Question 7: What is a shield launch shaft? It is a foundation pit or air shaft used for the launch of the shield machine.

Question 8: What is the difference between the shield launch shaft and the receiving shaft? The launch shaft must be equipped with a launch bracket and a reaction frame to facilitate the launch of the shield machine.

The receiving shaft should be equipped with a receiving bracket to facilitate the reception of the shield machine.

As for everything else, the structure and so on are pretty much the same.

Question 9: What is a shield inspection shaft? There is no word for shield manhole

Manhole is a vertical shaft built at certain distances on underground pipelines. It is mainly used for pipeline maintenance, sludge removal and connecting pipelines in different directions and heights. Specifically, they include flushing inspection wells, street inspection wells, water diversion inspection wells, sewage inspection wells, etc.

In comparison, the intermediate air shafts in shield tunneling projects are somewhat relevant

Subway In the project, the air shaft is responsible for the ventilation and drainage functions inside the subway tunnel. Currently, the ventilation of subway tunnels under construction can only rely on two fans to provide continuous ventilation. According to the engineering staff, if there are no ventilation measures, people will obviously feel that the air is not circulating and stuffy after entering the subway tunnel for 100 meters, and the temperature inside the tunnel will be much higher than outside because of the construction. Therefore, building air shafts earlier to allow air circulation can reduce the use of fans and lay a good foundation for future shield advancement. In addition, the air shaft also has the function of drainage, so the location of the air shaft is often the lowest-lying area in the entire subway section. Once groundwater appears inside the subway tunnel, the water can be quickly drained out by the water pump set in the middle air shaft. .

Question 10: What is a shield tunnel? To answer the shield tunnel, we must first talk about shield tunnel construction.

The shield construction method is a construction method for digging underground tunnels under the ground. It uses a shield machine to excavate underground to prevent the collapse of the soft foundation excavation surface or maintain the stability of the excavation surface. Tunnel excavation and lining operations are carried out safely inside the machine. The construction process requires that a shaft or foundation pit be excavated at one end of a certain section of the tunnel, and the shield machine be hoisted in for installation. The shield machine starts digging from the wall opening of the shaft or foundation pit and advances along the designed hole line until it reaches the hole. The endpoint of another shaft or tunnel in a line. When choosing a shield construction method, a detailed comparison of the characteristics of various shield construction methods is key. Among them, it is most important to select a shield machine type and reasonable auxiliary construction methods that are suitable for soil conditions and ensure the stability of the working surface. Therefore, the selection principle of shield machine is to adapt measures to local conditions, maximize the degree of mechanization, and reduce the impact on the environment.

The shaft that provides conditions for shield machine operations is called a shield shaft.