Hello all,
Thank you for your responses. I really appreciate the feedback. I wrote a quick summary, but also included the replies (shortened) below.
I'm sorry I couldn't reply to all of you individually.
Main summary:
· Upgrade anti-vibration legs
· There should be no danger to magnet itself, but its operation might be limited. Unless unshielded magnet with large fringe field.
· Digging, foundation work have worst effects. Potentially delay installation until foundations are set or construction has reached floor level of the NMR
· Anti-vibration cement slabs as further reinforcement under the NMR is recommended
· Expect cuts to power/air/water and be prepared for it
· Keep contact with Bruker and construction crew. Bruker should have tables with minimum distances for machinery and limits for their anti-vibration legs. Set up a perimeter outside, tell construction crew limits of vibrations and to give warnings for big events
· Make sure access to NMR is always possible, and construction knows that. Especially for cryogens
· Construction dust can get everywhere. Check location of air handler and use sticky mats in entrances.
Cheers
Alex
Alexander Funk, PhD
Chemist, Metabolomics Core
Institute of Clinical Chemistry & Laboratory Medicine
University Hospital Dresden
Fetscherstr. 74, 01307 Dresden
Germany
1) the modern building construction site, it will not have much impact on nearby NMRs. In past two years, there are two new connected building constructed next to our building with 7 NMRs from 400 to 700. We didn't get much impact. Of course, we are not running long experiments during the scheduled controlled explosion when they dig rock out for basement and foundations.
2) Do your magnets already have vibration dampener legs? If not this might be a worth while upgrade to help minimize the observed vibrations.
3) You could delay the install of your NMR instrumentation until the construction of the adjacent building has at least passed the floor where your NMR Facility is located.
Alternatively, a more costly approach may be to have the floor built to have some of its own vibration isolation (in addition to the anti-vibration offered by the pneumatic legs).
One of our NMR magnets is located in a annex wing that was designed with this magnet in mind. The floor is on grade (no basement below), and the slab under the magnet is isolated from the adjacent rooms. I don't know the specific details of what when into this design (it predated my arrival here), but if your construction hasn't progressed too far, you may want to look into this option.
Do you anticipate any disruptions to services (e.g. power, HVAC, compressed air/nitrogen) during the construction of the adjacent building. If so, make sure that they understand that you require advanced notice (we push for three weeks, and usually settle for two weeks notice).
When we had our facility built a while ago, the concrete slab that was poured was an anti-vibrational slab. It's actually been quite effective in dampening vibrational effects from nearby construction, as for the last few years, the construction crews (complete with cranes) were erecting a new building right next to ours.
Thanks to the anti-vibrational slab, I never noticed any disturbances when the construction crews were literally dropping tons of concrete, pipes, etc., on the ground near by.
In terms of magnets, we never noticed any issues either, although all of our magnets are shielded
5) There are several things to consider:
1. Vibration- When they are digging or blasting near the lab, are the critical times. Only short experiments should run during these periods.
2. Construction dust- How well sealed is the magnet lab from the dust and debris generated by the construction? The access to the construction site from your area of the building should be limited. Sticky mats near the lab entrance might be helpful to eliminate charged particles getting on/in the magnet. Proximity to the construction site for the air handler can be a concern.
3. Electrical/ air outages due to construction- You should have a safety plan in place for the emergency situation if electrical lines to the building are accidentally cut. Air can be an issue too. A positive air pressure in the lab will help with construction dust.
6) We have a Avance Bruker and we are right next to a train track and on the third floor. We haven't had any issues since all were discussed with architects.
7) I was at a site where we had a 600 in a basement lab and they were tearing down a 3 story building about 30 meters away. They were going to be pretty rough about it until I brought up the magnet and vibration issues. In the end they "picked" it apart more than just knocking it down. That said they lost control of a three story brick wall near the end of the demolition and it came down all at once and there was very little evidence of that in our lab. I had asked for them to install accelerometers in the NMR labs and I had asked Bruker for advice on tolerable limits and gave those to the contractors.
As I see it there are two issues one is impact on data and the other it the risk of vibration damaging the magnet. I suspect that damaging the magnet would be beyond most construction impacts.
8) First, make sure that you have 100% reliable access to the NMR lab at all times, particularly for deliveries of cryogens. You cannot afford to find out that you can't get cryogens to the lab when you need them (a week later will not do!). Make sure that the people involved fully understand this and the potential cost of resulting damage if you can't get the access you require.
Second, expect that at some point during a major construction programme, there may be some unplanned interruption to services. There is a significant likelihood that at some point the electricity will go off. It may not happen, but I have seen it happen too often not to consider it, so think about how much of a problem that is likely to be. If you are just running ambient temperature probes it may be just an inconvenience, but if you are running helium cryo-probes it could cause you major issues, so you may want to check that you have an adequate backup power supply to at least allow you to warm up the probe in a safe way if the power goes off. Obviously, you should already have that, but it is worth just checking and looking for an upgrade if necessary.
Third, your major problem, particularly in the early stages of construction, is likely to be vibration. I assume that your magnet(s) will already have vibration isolation legs, but they will not isolate the magnet from low frequency vibration, particularly from things like pile driving of foundations. Really all you can do about that is to try to plan your work to minimise the disruption. The major deleterious effects of vibration are observed in multi-dimensional experiments. I assume that construction work will only take place in the daytime. So if you have long 1D experiments to run (such as 1D carbon experiments) schedule them to run during the day and save the 2D stuff for overnight and weekends. It's not ideal, but it does give you the best chance of still getting useful data out of the instrument(s).
Hopefully, the serious disruption will not last for the whole 4 years. The early phase of the construction when they are excavating and laying the foundations should be the worst.
Finally, if the layout of your NMR lab is not yet finalised, try to make sure that the magnet is as far away from the construction site as possible. Even a few metres can have a significant effect. In particular, you do not want the magnet close to an external wall that is next to a site where they are likely to be lifting large steel girders into position (which is the kind of thing that tends to happen when they are erecting multi-storey buildings).
9) Dust, vibration, noise & moving (Magnetic) metal on the other side of the wall and minimising/eliminating their influence on the lab equipment & users, immediately come to mind.
also a few questions: It would be useful to know how many NMRs( is it one?); field strength?; nature of data collection ?(eg proteins for a week or faster turn around?); is it 24/7 operation? is it purely service lab or do users run their own? & then do they traffic through the building site?
Will services such as compressed air, gases He/N2, power, be effected and if so how? There's sometimes the unexpected power down/gas loss!? Will cryogen delivery be effected? does the air con feed from the building site?
10) Die Gerätehersteller geben in den site planning Unterlagen Tabellen mit Mindestabständen von Fahrzeugen u.ä. zu den Magneten an. Diesen Bereich habe ich absperren und mit Warnschildern versehen lassen. Solchen Tabellen wird meist auch eher geglaubt als den verantwortlichen Mitarbeitern.
Gegen die Schwingungen ist man damit nicht gefeit, da lässt sich aber u.U. an den Geräten etwas bei den Schwingungspufffern nachrüsten. Wir sind im EG untergebracht und die Magnete sitzen auf Betonwürfeln direkt auf dem Fels. Die Masse des Fundaments bringt auf jeden Fall auch schon einen Schutz. Was da bei euch im Elbkies geht muss der Bauphysiker entscheiden.
Empfehlen kann ich auf jeden Fall dringend auch USV und Überspannungsschutz, aber mglw. seid ihr da als Klinik schon ausgerüstet. Im Laufe des Aushebens der Baugrube wurde 3* die Stromleitung durchgebaggert.
11) My main worry was always vibrations from rock blasting. The discussions I could have with the magnet specialists at, in this case, Bruker was very valuable and comforting. A modern magnet is quite robust. Blasting should be planned in time, and magnitude to be as safe as possible, and with as little intrusion to ongoing work. This was the my main concern regarding damage to the NMR systems, but of course for the operation there are more potential problems. You might not need rock blasting in Dresden, but impalement instead. Power failure from mistakes on the building sites. Lower intensity vibrations from mentioned impalement, heavy traffic, and machine work. Dust from the building site. Gas supply disturbance.
I think you would have a lot to gain, just by going through the construction plan with the responsible site manager, and make them fully aware of the sensitivity of your equipment, the need for long time experiment, the high cost of operation. An interuption in the NMR schedule is not too bad, but continuous disturbances causing less then optimal data is very frustrating, and expensive.
12) Es hängt natürlich viel davon ab, was für Spektrometer du hast. Da ist einmal die potenzielle Störung deines Magnetfelds durch riesige bewegte Metallmassen (Kräne, Bagger, Lastwagen, Rohre, etc.) zum anderen sollte man die Erschütterungen bei großen Bauarbeiten nicht unterschätzen. Als wir in Utrecht alle unsere Instrumente (alle Bruker) in eine neue große Halle umgezogen hatten, haben sie am anderen Ende des Campus(!) einen Neubau begonnen. Das ist vielleicht nicht völlig vergleichbar, weil sie in Holland praktisch alles auf Sand bauen und darum riesige Betonpfeiler in den Boden rammen müssen, aber die Erschütterungen konnten wir über mehrere 100m Entfernung in unserer NMR-Halle messen. Wenn der Neubau wirklich Wand an Wand geschieht, können Starkstromkabel ein weiteres potenzielles Problem darstellen. Offensichtlich kann ich dir nicht wirklich Lösungen anbieten, aber Bruker (bei uns) hatte einige gute technische Lösungen zur Hand (spezielle Anti-Vibrationsfüße, z.B.). Ich denke dann auch, dass Du den Hersteller deiner NMRs bei dieser Sache einbeziehen solltest (falls dies nicht sowieso schon geschehen ist).
13) We lost an unshielded 600 magnet a couple of years ago during a construction project. The magnet quenched over a weekend, so we weren't exactly sure what happened, but it was most likely due to the movement of a large construction vehicle past the magnet. The quench occurred even though the construction vehicles were moving beyond the distance where we could detect any increase in magnetic field due to the magnet. During a previous construction project, we had run a test of the effect on the lock level of the movement of a large construction vehicle past the magnet. Even at a distance where the magnet field could not be picked up by our Gauss meter, we measured a large drop in the lock level of the unlocked magnet when the construction vehicle drove past the magnet.
I would recommend that you avoid allowing any large construction vehicles, e.g., dump trumps, cranes, cement mixers, etc. to drive anywhere near the magnet. Next month, we are scheduled to have a new sidewalk constructed behind our building and have worked with our facilities personal to have the cement offloaded from the cement mixers to smaller vehicle for the sidewalk installation.
Received on Mon Oct 14 2019 - 06:03:36 MST