Tunnel Boring Machine (TBM) method

A tunnel boring machine (TBM) also known as a “mole”, is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They can bore through hard rock, sand, and almost anything in between. Tunnel diameters can range from a metre (done with micro-TBMs) to almost 16 metres to date. Tunnels of less than a metre or so in diameter are typically done using trenchless construction methods or horizontal directional drilling rather than TBMs.

Tunnel boring machines are used as an alternative to drilling and blasting (D&B) methods in rock and conventional “hand mining” in soil. TBMs have the advantages of limiting the disturbance to the surrounding ground and producing a smooth (гладкий, ровный) tunnel wall. This significantly reduces the cost of lining the tunnel, and makes them suitable to use in heavily urbanized areas. The major disadvantage is high cost. TBMs are expensive to construct, and can be difficult to transport. However, as modern tunnels become longer, the cost of tunnel boring machines versus (в сравнении с)drill and blast is actually less – this is because tunnelling with TBMs is much more efficient and results in a shorter project.

The largest diameter TBM, at 15.43 m, was built by Herrenknecht AG for a recent project in Shanghai, China. The machine was built to bore through soft ground including sand and clay. The largest diameter hard rock TBM, at 14.4 m, was manufactured by The Robbins Company for Canada’s Niagara Tunnel Project. The machine is currently boring a hydroelectric tunnel beneath Niagara Falls.

Match the words in A with their synonyms in B. Write down the answers.

A B

1. manually	1. to drill
2. to utilize, to apply	2. to include
3. important	3. to use
4. to bore	4. to supply
5. to comprise	5. by hand
6. to provide	6. to take into consideration
7. to take into account	7. significant

Match the words in A with their antonyms in B. Write down the answers.

A B

1. vertical	1. undetonated
2. hard	2. permanent
3. expensive	3. horizontal
4. risky	4. cheap
5. detonated	5. safe
6. temporary	6. easy, soft
7. deep	7. unlike
8. like	8. shallow

2.16. Click here to watch the video how TBM works in hard rock:

http://www.youtube.com/watch?v=yFHrI3HFMDg&feature=related

2.17. Read the text “What is trenchless technology? ” and decide if the folloing statesments are true or false.

1. The term “trenchless technology” refers to the techniques and methods when we need to build a new traffic tunnel underground.

2. There are more advantages when we use trenchless technology than disadvantages.

3. Trenchless technology, as compared to other methods, is simpler because it does not involve complex processes and skilled manpower.

4. But it consumes a lot of time when it comes to construction.

5. Trenchless technology is actually becoming the trend now among many cities worldwide.

What is trenchless technology?

The term “trenchless technology” refers to the techniques and methods when it comes to repair, installation, modification, and rehabilitation (реконструкция) of pipes and cables underground minus the disturbance (нарушение) that it creates on the structures above.

Trenchless technology is actually being used in developed cities in order to eliminate the problems when it comes to cable wires and water systems. There are actually a lot of advantages when it comes to the use of trenchless technology and the following are the examples of the advantages of the use of trenchless technology.

One of the main advantages of using trenchless technology is that since the pipes, cables, and other stuff are located underground, we may be able to avoid disrupting the traffic above. Plus there is also no space wasted above for the pipelines and cables unlike when the latters are above the ground.

Another advantage of using trenchless technology is that it does not waste any resources since the street that has been dug up actually need not to be fixed or rebuilt.

Trenchless technology, as compared to other methods, is way simpler since it does not involve complex processes and skilled manpower. It does not also consume a lot of time when it comes to construction because it is very easy and quick to complete.

Trenchless technology is also known as the “no dig” technology and it is actually becoming the trend now among many cities because of all the benefits and advantages that come with the use of it.

If there is one disadvantage when it comes to the use of trenchless technology, which is the fact that the equipment or tools that are used in construction as well as the maintenance are very costly. Up until this time, this obstacle is the only reason on why other cities do not adapt this technology.

Дата добавления: 2015-10-31