Suggestions for setting approx 100 monitoring points in concrete block walls on top and bottom of walls. Thinking reflective stickers with some kind of waterproof epoxy because the surface is not flat, and the walls are usually wet(Seattle). Most of the tops can set a lead and tack. In some areas thinking of using Benchtie nails in the cracks on some of the bottoms of walls due to not having much space away from walls to see the reflective stickers. Points are to be monitored for at least 3 years so semi permanent points. Thanks in advance!
For things in the face of the wall, 1/4" drill hole with 1-1/2" mag nail (big head). A little epoxy in the hole to keep things in place. Tie reflectorless. Stickers work great for shorter term but 3 years is likely too long.
Avoid setting anything in any cracks. As Mark says, drill a hole. Check for any chalking or delam by tapoung with a hammer. If it makes a dull thud or high pitch clack find a better spot. After that, screw it up EXACTLY the same way every time...
Berntsen make a small tilting prisim setup with an adapter I wonder if you could by a bunch of adapters and just move the prisim around. They also make a retro reflective version of this that is a lot cheaper. https://www.berntsen.com/Surveying/Survey-Prisms/Specialty-Prisms/ctl/ViewProduct/mid/1611/itemID/1634
Trimble sell a 25mm prism (part number 58008030) on a simple swivel mount that is designed for monitoring.
We use them a lot around our port and other monitoring jobs
Set a wall anchor, attach the prism, point in the correct direction and leave them there
You can get them in a http://www.survey-solutions-scotland.co.uk/shop/proddetail.php?prod=58008030&apos ;">box of 25
Not particularly cheap - but if the client is paying disbursements that's not your problem
I'm a fan of the products from Rothbucher Systems
https://www.meterriss.de/images/PDF/PP_us.pdf
I do quite a bit of long term wall monitoring. On high walls (tamper-prof) we set permanent monitoring prisms. The are in the $100+ range if you get them form Leica, Trimble or Seco. I usually but a couple of hundred at a time from China for about $35 each. On lower points that are easier to get to and more likely to be tampered with I use a removable prism. A monument I use is similar to the Berntsen copper plugs but with an 8mm threaded center hole. When on site I then insert the complimentary prism mount in the monument. Neither of these are cheap to acquire or install, but if it needs to be correct it is worth the time and cost.
Trimble sell a 25mm prism (part number 58008030) on a simple swivel mount that is designed for monitoring.
We use them a lot around our port and other monitoring jobs
Set a wall anchor, attach the prism, point in the correct direction and leave them there
You can get them in a http://www.survey-solutions-scotland.co.uk/shop/proddetail.php?prod=58008030&apos ;">box of 25
Not particularly cheap - but if the client is paying disbursements that's not your problem
Jim.Cox's link is broken - here is a corrected version:?ÿ?ÿ http://www.survey-solutions-scotland.co.uk/shop/proddetail.php?prod=58008030
I do like the?ÿRothbucher Systems items as mentioned by James Fleming.?ÿ If I were into such monitoring, I can see being very interested in said items.
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For monitoring the wall in the photo we used tiles purchased in sheets from Home depot and attached reflective stickers from Berntsen.?ÿ The tile was then Liquid Nailed to the gabion baskets and read by total station from the vantage point of the photo. They showed no sign of deterioration in the year we used them and I think the County still uses them several years later.