Sunday, March 24, 2013

A Tunnel Boring Machine (TBM) Breakthrough Ceremony

I've been remiss in cranking out blog entries.  I took a job with my old friends who are currently working on digging a water supply tunnel near Kuala Lumpur.  (See last year's blog entry about the tunnel.)  I've been too busy (tired, actually)!  I'm working part-time with the joint venture construction company that's building the tunnel, helping them with technical documentation for constructions claims.  (I'm waa---aaay too old to be working inside a tunnel site!)

This past Friday, we had a really impressive ceremony to mark the completion a tunnel stretch being excavated by one of our three tunnel boring machines (TBMs).  I've got a cool (short) video for you to watch!

First, some background.  This tunnel, a part of the Pahang Selangor Raw Water Transfer project, will deliver water from the Malaysian state of Pahang (which has lots and lots of rivers and water) over the mountains to the neighboring state of Selangor, where Kuala Lumpur and other population centers are located.  It is a classic "interbasin" water transfer project.  You engineers, earth scientists and other techies reading this can download this past issue (PDF file) of the magazine of the Board of Engineers Malaysia and read about the project starting on Page 42 onward.  The construction is funded 75% by Japanese aid, and 25% from Malaysian government funds.

Location Map

The tunnel is 44.6 km long. This makes it the longest tunnel in Southeast Asia, 11th longest in the world, and with the 8th highest overburden (height of ground above tunnel --- 1,246 meters in this case) in the world. The TBMs are gouging a 5.2 meter diameter tunnel through some pretty hard granitic formations.

Oh, by the way, don't let anybody tell you US companies can't compete overseas! The three TBMs in use here were designed and built to this project's specs by The Robbins Company of Solon, OH. Their PR hacks were here in droves to record the breakthrough (while the poor Robbins tunnel guys were slaving away at their TBM). Robbins is reckoned to be best of their class for the "hard-rock" TBMs, while their German competitors are reckoned to be better for "soft-rock (shield)" TBMs.

TBM Excavation Directions and Progress to Date

Of the 44.6 km of the tunnel, 34.5 km are being excavated by three TBMs. The rest (the red parts on the figure) were excavated by conventional drilling-and-blasting or by cut-and-cover.  As you can see from the figure above, TBM-1 is excavating downstream from the Pahang side, while TBMs 2 and 3 are excavating upstream from Selangor towards Pahang. It was TBM-3 that just completed its 28-month, 11.6 km run.  The other two have several more months to go.

VIPs ranging from senior Malaysian government officials, the Japanese ambassador (remember the funding source?), the design/construction supervision engineers, and invited guests like press, staff from subcontractors and suppliers, neighbors, local government folks, etc., were bused down "Adit 4" (access tunnel #4) that carried us down to the breakthrough spot.  Without further ado, here's what happened --- watch the video:

(In case you can't see the video in the box above, go to:

The VIPs in the front were covered with dust, but pretty soon they forgot the dust as the TBM-3 crew started emerging from the cutterhead that had just broken through:

Waving Malaysian flags, the TBM crew in red coveralls, the Malaysian geologist, Japanese and Indonesian tunnel engineers, and that Robbins guy in blue all emerged from a tiny maintenance hole in the cutterhead.  A Japanese kiyome site purification ceremony followed, with Japanese tunnel engineers from the two Japanese contractors in the joint venture "anointing" the exposed TBM-3 cutter head with salt, rice grains, and sake rice wine.  Then the VIPs started speechifying --- we'll skip that part.

After the speeches, the photo opportunities started.  For more than an hour after the speeches, long after the VIPs and most of the invited guests returned to the surface for a sumptuous buffet lunch, folks were taking pictures. First, the TBM crews that worked in the TBM-3 tunnel posed with the cutting face (strangely reminiscent of the sandworms of Dune.)

The tunnel engineers from the Japanese contractors broke out some Japanese flags.  With some of them clad in traditional happi coats for festive occasions, they roar their triumph with their Malaysian, Indonesian, and Bangladeshi staff.  The crews of TBMs 1 and 2, who will not have a public "breakthrough ceremony" like this when their tunnels meet towards the end of the year, also join in for a picture at the cutting face:

Before going up to see what's left to eat of the fancy buffet that's been laid out at the surface (courtesy of the Japanese Embassy), chief geologist Frank Pittard from the UK poses for a triumphant picture with his staff of Malaysian geologists.  Every day, without fail for almost three years, they've been mapping every inch of the rocks that haven been exposed by the excavation in various tunnels , determining what type of supports the engineers needed to keep the newly-excavated tunnel sections from collapsing:

Anyway, on behalf of Pat and myself, I'd like to say "hi" to our readers, and we look forward to seeing many of you in a couple of months' time back in Michigan! Please make sure the snow is gone by the time we get back! Cheers!


  1. this is a very intresting writing as I am a gtechhnical person myself.

    Do you really have a second home in Malaysia? I would be intereted to know about this sescond home if O may get your email. Mine is

  2. A horizontal boring machine is a time-saver machine used to bore holes in highly rigid construction. Thanks for sharing this useful post.

    Himes Machinery