Looking good, I have spent some time working on tunnels also.?ÿ
I am interested in learning more about how other people set fiducials.
I have heard that when you order a Heerenknecht machine equipped with VMT that the spigots come installed and that you just need to survey the machine and fiducials and drop the NEZ into VMT.?ÿ
I have used TACS, ZED, and Enzan but never VMT.?ÿ
?ÿ
We're using CAP as its a subsidiary, most people at work say VMT is really good (I've not used it).
If you look at (picture 2) you can see some retros which we used. CAPs own surveyors went to HK factory in Germany and surveys a bunch of retros they placed on the H-frame to coordinate them to the machine.
Once the TBM was reassembled on site, we welded reference prisms on then surveyed those with the retros. CAP then used the retros to coordinated the offset values for the prisms relative to the TBM from their survey at HK.
Thanks for sharing, it looks like the operations are clean and safe! Good for you guys for keeping an operation that you can take pictures of without it looking like a disaster.
No gyro used? How long was your start reference line? I did some tunneling before and was always anxious to know if they would show up where they needed to be.
Not these kind of tunnels but 2m diameter in curbs for a few hundred meters. Exciting but stressful jobs
I did some gyro azimuths for a pair of hydro tunnels in Peru, they had me come in when they were getting close to breakthrough, drilling from both ends. I think one was 22 km and the other a bit less. Had a bit of a water problem...
We had to ride in the mine cars to get to the face, about 45 minutes each way
Here was their "low-tech" TBM guide target, as long as the laser was inside the hole, they were online
I had to observe a surface line to calibrate, on triangulation pillars
The TBM was nowhere as clean looking. They actually got one of them stuck, and had to bring in another one to clear a path to get it out.?ÿ
They sent me pics when they broke through, not sure what I did with those.?ÿ
I did some gyro azimuths for a pair of hydro tunnels in Peru, they had me come in when they were getting close to breakthrough, drilling from both ends. I think one was 22 km and the other a bit less. Had a bit of a water problem...
We had to ride in the mine cars to get to the face, about 45 minutes each way
Here was their "low-tech" TBM guide target, as long as the laser was inside the hole, they were online
I had to observe a surface line to calibrate, on triangulation pillars
The TBM was nowhere as clean looking. They actually got one of them stuck, and had to bring in another one to clear a path to get it out.?ÿ
They sent me pics when they broke through, not sure what I did with those.?ÿ
?ÿ
Awesome. Never worked with a gyro myself, that's true surveying. I love it!
We won't use a gyro on this one in the pictures the first two drives are only 1.6km per drive, the alignment is almost a straight line too. Did some astro-shots on the external control, just for self development/curiosity exercise as I heard its more accurate and we never covered that when I went to university (still got to process it).
The second two drives?ÿare?ÿabout 6km per drive, curved alignment. We'll use a gyro, start, midway and one?ÿjust?ÿenough?ÿbefore breakthrough?ÿprobably.?ÿ
Start reference was about 500 metres on the first drives, got the benefit to start it from a very open cutting in the countryside.?ÿ
The water does look a bit of a problem and?ÿI'm very impressed with those guide targets!?ÿ
Looks like a great experience to have had like an expedition. Would love to work abroad in South America at some point, been to Peru and Ecuador before and loved it.
