We have been asked to (but not awarded) stake some items on a coral atoll. There will be RPs in areas with crushed coral over coral (I don't know how deep the crushed coral is) as well as exposed coral. There may be some dirt (but I think that it's relatively thin) covering.... you guessed it... coral.
I searched the site for info on this and didn't come up with anything helpful (lots of info on coral snakes and the Coral Sea.)
Doesn't seem like the standard RPs I'm used to: hubs, rebar, PK nails/mag nails, spikes (even chiseled "X"s) will work well when there's 6" of crushed coral on top of coral.
Can you set a 3" magnail at a specified location in coral or does the coral crumble and the nail moves around?
How do you mark the RP? - lath won't work - you can write the c/f rp dist on the flagging but that requires the end user to pick up the flagging to read - not very efficient.
For those that work in these environs - what do you set for RPs with this type of "ground"? I'm looking for quick, stable, and controllable (cheap is not nearly as important).
Thanks...
I have no experience in setting RP's in coral beyond coconuts and pina coladas. My solution would be to use galvanized metal pipe, maybe 1-1 1/2" diameter, cut at an angle to encourage penetration and driven to refusal and then cut off just above ground level. A lath or other similar wood stake could then be driven into the open end of the pipe and inscribed as called for. Wood disappears in a typhoon and pipe buried under shifting coral sands they should be secure and easily found with a metal detector. If it's solid coral that requires penetrating a cordless rotohammer should do the trick as it's only calcium carbonate and not all that terribly dense.?ÿ
These are just temporary stakes for construction ?
Yes these are temporary points for construction.
They may need to last as long as 2 or 3 months but wouldn't be subject to traffic (vehicular or pedestrian). They may be subject to molestation by birds!
A possible problem with that large of a pipe is that the construction crews may decide to measure off the face instead of the center.?ÿ If that difference is significant to the project, you may have to put a plug in the pipe with a tack so it looks like a measurement point, and tie the lath to the pipe to give them the numbers instead of putting it in the pipe.
Yes these are temporary points for construction.
They may need to last as long as 2 or 3 months but wouldn't be subject to traffic (vehicular or pedestrian). They may be subject to molestation by birds!
Spitballing here; what about bamboo painted up like a story pole ???ÿ
I have no experience in setting RP's in coral beyond coconuts and pina coladas. My solution would be to use galvanized metal pipe, maybe 1-1 1/2" diameter, cut at an angle to encourage penetration and driven to refusal and then cut off just above ground level. A lath or other similar wood stake could then be driven into the open end of the pipe and inscribed as called for. Wood disappears in a typhoon and pipe buried under shifting coral sands they should be secure and easily found with a metal detector. If it's solid coral that requires penetrating a cordless rotohammer should do the trick as it's only calcium carbonate and not all that terribly dense.?ÿ
This may work - it would be a lot of material to carry around and we'd skip the cutting it off part...
Hopefully there's a lighter, less labor intensive (cutting up all the pipe) commercial solution...
Wire flags set in small diameter drill holes in the solid coral?
Something along these lines, maybe?
https://www.berntsen.com/Surveying/Survey-Monuments/FENO-Survey-Monument/FENO-Spike
?ÿ
Whatever you come up with is going to have to be both sharp and stout to penetrate coral through sand.
I bought a gas powered jackhammer on Amazon for $250. It came with two bits, one pointed and one chisel. I've since bought a shovel bit and a wider chisel bit for cutting asphalt. The small chisel bit makes a hole 8 inches deep perfect fit for a stake. The jackhammer is a little chinsy made, but for $250 what can you expect. It bores through rock hard dried gumbo like hot butter. You write the stake pound it into the hole and it'll be there forever. A secondary use turned out to be digging up monuments in the middle of gravel roads. Throw away the digging bar. This little jackhammer with the shovel bit digs them up in minutes. It's Chinese made(no offense to any Asians) so it may not last long, but in one month it paid for itself four or five times. Light enough for one man to tout around. Lots of plastic so you do have be careful how you transport it, but the bits a harden steel and the business end of it is cast iron. For $150 an hour I fly to your location and set your stakes for you. It's 18 degrees here right now. Any place wit coral has got to be alot warmer.
Cordless rotary hammer, small bit and painted bamboo.?ÿ A little nicer on the environment than a gas hammer and the eventually the bamboo will wash away.
