In today's society, whether it is subways, high-speed rails or trains, the routes they travel must pass through some tunnels in the middle. Everyone knows that there is no light in the tunnels and the surroundings are dark. The editor thought, why is there no light in the tunnel? If there is no light, how was this tunnel built? Therefore, in order to understand the confusion, I searched the Internet for information and learned some relevant knowledge. The following editor will share this knowledge with you, namely, tunnel construction methods, classifications, steps, and tunnel excavation methods?
What is the tunnel construction method? Because the angle of consideration is different, the construction method will also be different. If considering the construction cost and speed, the full-face excavation method should be selected; and from the perspective of construction safety, the double-sided pilot pit method should be selected. As for the specific construction steps of these two methods, the following editor will explain in detail for everyone.
What are the construction steps of tunnel engineering? Different construction methods, their construction steps are also different, the following editor will use the full-section excavation method and the double-side wall method to explain in detail.
Construction steps of full-face excavation method: mechanized construction of tunnels, with three main lines of operation.
Step 1: The first line is the excavation line. Drilling trolley, charging trolley, loader with dump truck (trackless transportation), slag loading machine with mining car and battery car or diesel locomotive (railway transportation).
Step 2: The second line is the anchor spray line. Concrete spraying machine, concrete spraying manipulator, anchor spraying work platform, feeding and transportation equipment and bolt grouting equipment.
Step 3: The third operation line is the molding line. Concrete mixing equipment, concrete transport truck and pump, waterproof layer work platform, lining steel mold trolley.
The construction steps of the double-side pilot tunnel method:
Step 1: Excavate a pilot pit on one side and close it for the first time in time.
Step 2: Excavate the pilot pit on the other side after a proper distance, and construct the primary support.
Step 3: Excavate the upper core soil, construct the first support of the arch, and support the arch feet on the first support of the pilot pits on both sides.
Step 4: Excavate the lower steps, construct the first support at the bottom, and close the full section of the first support.
Step 5: Remove the first support of the empty part of the pilot pit.
Step 6: Build the inner lining.
Tunnel engineering classification:
1. According to the purpose
1) Traffic tunnel engineering: provide transportation tunnels and passages, including railway tunnels, highway tunnels, underwater tunnels, underground railways, and pedestrian tunnels.
2) Hydraulic tunnel engineering: It is an important part of water conservancy projects and hydropower junctions. Mainly include diversion tunnel, tailrace tunnel, diversion tunnel (flood discharge tunnel), and sand tunnel.
3) Municipal tunnel project: it is an underground tunnel for the placement of various municipal facilities in the city. There are mainly water supply tunnels, sewage tunnels, pipeline tunnels, line tunnels, and air defense tunnels.
4) Mine tunnel engineering: its role is mainly to serve mining. Mainly include transportation lanes, water supply tunnels, and ventilation tunnels.
2. According to the length of the tunnel
1) Extra-long tunnel: L>3000 m;
2) Long tunnel: 3000 m≥L>1000 m;
3) Medium and long tunnel: 1000 m≥L>500 m;
4) Short tunnel: L≤500 m.
3. Divided according to the geographical location of the tunnel: mountain tunnel, underwater tunnel, urban tunnel.
What are the tunnel excavation methods? The excavation method is divided into open excavation method and underground excavation method. The open-cut method is mostly used in shallow-buried tunnels or urban railway tunnels, while the mountain railway tunnels are mostly used in underground excavation. According to the size and location of the excavation section, there are partial excavation method and full-section excavation method. Drilling and blasting is the most widely used method in rock formations, and the use of roadheaders for direct excavation is gradually popularized. Shield excavation is often used in soft geology.
