Chinese-built underwater tunnel drilled through in Bangladesh.

[Abu Shaleh Rumi]

 

[F-6 enthusiast]

This is from 1 year ago but informative.

more recent video

 

[Bilal9]

Congrats to all involved! Wonderful achievement and completed seven months AHEAD OF SCHEDULE and Under Budget. Yay !!

Hope we can re-use the tunnel borer in our upcoming Metro 5 line tunnel but that is a Japanese project.

 

[bluesky]

Hope we can re-use the tunnel borer in our upcoming Metro 5 line tunnel but that is a Japanese project.

If I can read the Japanese mind truly, they will not use anything Chinese or anything produced in other countries and not any used ones. They will cite many reasons and some are valid. One is they are not familiar with a non-Japanese machine and may face operating problems, there may be an accident or the machine may bog down.

Japan will certainly use its own Shield boring machine. And after its use, it may sell to a local company or to a govt body. The same may be true for the Chinese one. I personally would like to see our own companies start doing this kind of tunnel boring by themselves in the next projects.

But will there be other projects in the future, although I can foresee quite a few projects in our Ctg. Hill Tracts area for the expansion of the road system? If there is no buyer, the Chinese will ship the machine back to their homeland which has many tunneling jobs.

A Singapore leasing company may also buy it.

 

[Bilal9]

If I can read the Japanese mind truly, they will not use anything Chinese or anything produced in other countries and not any used ones. They will cite many reasons and some are valid. One is they are not familiar with a non-Japanese machine and may face operating problems, there may be an accident or the machine may bog down.

Japan will certainly use its own Shield boring machine. And after its use, it may sell to a local company or to a govt body. The same may be true for the Chinese one. I personally would like to see our own companies start doing this kind of tunnel boring by themselves in the next projects.

But will there be other projects in the future, although I can foresee quite a few projects in our Ctg. Hill Tracts area for the expansion of the road system? If there is no buyer, the Chinese will ship the machine back to their homeland which has many tunneling jobs.

A Singapore leasing company may also buy it.

@bluesky bhai,

There are at least two river crossing projects that I know of, that plans to use tunnels, rather than build bridges. There is a third - a crossing of the Padma also planned using a tunnel, in a different spot. I am sure we well hear of more.

Boring tunnels under rivers is actually far easier and completed much quicker than by building a bridge. Karnaphuli tunnel was completed in two or three years I believe (after work started) whereas the Padma Bridge took significantly longer and had many interesting (and expensive) challenges, such as piling work for the bridge footers which is the deepest undertaken for a river bridge I believe (122m). A tunnel simply bores a way from one side of the river to the next. But 6/7 km is a long way to go for a tunnel under Padma Bridge - which would be quite expensive.

Three records of Padma Bridge

Three records of Padma Bridge

www.daily-sun.com

 

[The Terminator]

Congrats to all involved! Wonderful achievement and completed seven months AHEAD OF SCHEDULE and Under Budget. Yay !!

Hope we can re-use the tunnel borer in our upcoming Metro 5 line tunnel but that is a Japanese project.

Chinese machinery being used in Japanese project! It would never happen. Lol
The Japanese would commit suicide before using Chinese machinery

 

[bluesky]

A tunnel simply bores a way from one side of the river to the next. But 6/7 km is a long way to go for a tunnel under Padma Bridge - which would be quite expensive.

A tunnel may be prohibitively expensive to construct compared to a truss bridge on top of piles. For example, the two tunnels bored 50 km through the English Channel bed cost 14.7 billion English Pounds in 1974. In today's money, the sum is about 33 billion Pounds which is about $45billion.

For a 6.5 km Padma crossing, the cost of constructing two parallel tunnels will at least be $5.9 billion. To me, it is not very lucrative.

I had no opportunity to be involved in tunnel construction, but being a cautious person, I would say the silt base may be weak to support the heavy vertical loads. Vertical loads will tend to bend the bottom slab downward here and there that can potentially break the base.

It could have been averted had there been a presence of dense and strong soil (a mix of sand, silt, and clay) below. But Padma soil is loose silt with weak shearing force. Arrangement of piling below the bottom slab may be an option, but no project ever did it and the cost is too high.

By the way, beautification is not the way to develop. A project must be able to pay back the costs with interest within two decades. However you say, even the Padma Bridge will not be able to pay back the incurred loans in the next 50 years.

Anyway, I have put only my personal opinion in this post. I am unable to influence even the dreamy minds of many posters here in this Forum, let alone swaying the mind of Hasina Bibi.

All that glitters is not gold. We should cut our clothes according to our necessities. I wish BD not to follow in the footsteps of Pakistan. We forget that BD still remains an underdeveloped 3rd world country without the presence of a strong industrial base.

 

[Bilal9]

A tunnel may be prohibitively expensive to construct compared to a truss bridge on top of piles. For example, the two tunnels bored 50 km through the English Channel bed cost 14.7 billion English Pounds in 1974. In today's money, the sum is about 33 billion Pounds which is about $45billion.

For a 6.5 km Padma crossing, the cost of constructing two parallel tunnels will at least be $5.9 billion. To me, it is not very lucrative.

You are right. Padma Bridge cost is roughly US$ 3.5 Billion or Tk. 30,193 crore (i.e. Tk. 302 Billion). This was as of 2018. I am sure cost has ballooned even more by now. Still cheaper than tunnels.

Padma bridge cost to rise again

The cost of the much-hyped Padma Bridge project is going to increase again as the government has to spend more to acquire additional land, taking the total project cost to Tk 30,193 crore.

www.thedailystar.net

I guess shorter distance like Karnaphuli crossing, tunnels may be more feasible.

 

[Beast]

If I can read the Japanese mind truly, they will not use anything Chinese or anything produced in other countries and not any used ones. They will cite many reasons and some are valid. One is they are not familiar with a non-Japanese machine and may face operating problems, there may be an accident or the machine may bog down.

Japan will certainly use its own Shield boring machine. And after its use, it may sell to a local company or to a govt body. The same may be true for the Chinese one. I personally would like to see our own companies start doing this kind of tunnel boring by themselves in the next projects.

But will there be other projects in the future, although I can foresee quite a few projects in our Ctg. Hill Tracts area for the expansion of the road system? If there is no buyer, the Chinese will ship the machine back to their homeland which has many tunneling jobs.

A Singapore leasing company may also buy it.

That is why Japanese infrastructure project are no more desire worldwide. Chinese project are leading the world infrastructure project with most cost efficient while without compromise safety.

 

[bluesky]

That is why Japanese infrastructure project are no more desire worldwide. Chinese project are leading the world infrastructure project with most cost efficient while without compromise safety.

Do not please forget that it is Japan that has led Asian countries in development since 1868. No wonder, the Japanese are proud of their achievements. Japanese would certainly use their own Shield tunneling machine in any project in BD.

Regarding infrastructure construction, Japan cannot do it alone throughout Asia and Africa because its currency is very strong, it has fewer people to do international jobs because of a dwindling population.

By the way, have you ever seen American companies doing international projects? I have not seen one. But, Japanese companies regularly do them because it is their responsibility towards Asia even though Japanese technical/ engineering manpower costs much higher than the Chinese ones.

One example is Dhaka Metro. It is a great project being done with JICA funds.

 

[Beast]

Do not please forget that it is Japan that has led Asian countries in development since 1868. No wonder, the Japanese are proud of their achievements. Japanese would certainly use their own Shield tunneling machine in any project in BD.

Regarding infrastructure construction, Japan cannot do it alone throughout Asia and Africa because its currency is very strong, it has fewer people to do international jobs because of a dwindling population.

By the way, have you ever seen American companies doing international projects? I have not seen one. But, Japanese companies regularly do them because it is their responsibility towards Asia even though Japanese technical/ engineering manpower costs much higher than the Chinese ones.

One example is Dhaka Metro. It is a great project being done with JICA funds.

My advise, dont dwell on history. Live in future! China is the future and China is the leader of Asia. No doubt.