Connecticut Land Surveyors group forum is for professional land surveyors in Connecticut, CALS members and LSU members who live and work in the state of Connecticut, USA to connect and share experiences.
Does anybody have any idea on how much frost affects monumentation? I have always wondered how much an iron pin or concrete monument could move based on frost. I survey in Connecticut, where the code deems frost depth at 42", but concrete monuments are only 30" and iron pins are accepted at 24", so frost must have an affect.
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It surely seems that the answer to the question "Does anybody have any idea on how much frost affects monumentation?" is "it depends on a host of other factors". I enjoyed all the reply comments and look forward to more. Your facts and opinions are important to the land surveying profession. Where else have you seen this topic discussed and viewed over 500 times online in a matter of 5 days? Many thanks to all.
Scott D. Warner, RLS
Senior Director / Editor
Land Surveyors United
As an afterthought...the effect of frost on monumentation is that the monuments get cold.
David,
Sorry for the delayed response, as I am doing things in order of importance. Low as this is on my list of comments to reply to, I must agree with your assessment that monuments really do get cold in the presence of frost.
When I was a child in elementary school, I discovered that iron pipes (a/k/a monkey bars) were dangerous; dangerous not only in the heat of Summer, but in the cold of Winter as well.
Yes, I was one of "those kids" who accepted the challenge of placing my wet tongue on a frozen iron pipe, which happened to be at about tongue level for me at the time. Needless to say, I was the last one in the door for class, and the only one with a mouth and face full of embarassing blood.
I got the full nine for this one. I got to meet the Principal for the first time, I saw the school Nurse for the first time, and I also got to hear things from my Parents I had never heard before.
Perhaps I should have waited until December to reply, when "A Christmas Story" can be seen on most local TV networks.
Well, at least it was the monkey bars and not the flagpole! :)
-Scott D. Warner, RLS
Surveying colleagues - what can I say. In South Africa, we hardly ever experience heavy snow, let alone frost to the extent you are talking about.
What I have witness personally though is benchmarks (height referencing) in clay "rising and falling" with variations in the moisture content of clay.
Position wise it did not make any significant difference, but definitely in terms of the height. The benchmarks had to be re-levelled almost every two to three days.
Interesting to read that the term monuments are used where here in SA we use the term beacons (to demarcate property boundaries) or reference marks if it is used in construction and the point has co-ordinates and height.
Hendrik Hugo
I have seen the same thing as well here. The clay formation is called "Haldimand Clay". It is kind of the same theory except that instead of the expansion force coming from temperature differential, when the clay gets wet it excites an electrical force (called colloidal force - I think - someone stole my Geotec book) which causes the clay particles to push away from each other, thus causing swelling.
In the summer when it is dry, you can pull the bars up with two fingers because the clay has shrunk from around the bar.
Hey, I think I have a picture of a B.L.M. Rail Road monument that is jacked out of the ground close to 10 feet. Look threw my pictures.... We use rods that are about 3.5 feet long and jackhammer (Punjar) them into ground and than screw another section and drive that down than add (screw on) another section and so on... Until we meet major resistance. Older rebars here jack out of the ground all the time... but never all the way. we always step on the rebar, Rarely do they ever move horizontally.
I found monuments that survived the 1962 earthquake and they moved vertically 17 feet but not horizontally... Check out my pictures...
Frost heave occurs when ground freezes to a point below the embedded object. The water in the soil expands when frozen. (Those of you in warmer climes can test this out by sticking a full water bottle in your deep freezer - don't blame me for any damage though!) The force of the water expansion pushes against the object, and if not restrained by friction or self weight the object will move in the unrestrained direction, which is usually up.
The freezing force is quite powerful and can also be applied to building footings, foundations, etc.
The minimum cover for most structural items in Southern Ontario, Canada is 1.2m (4').
We plant one 1" square smooth iron bars 4' long for every 3 smaller 3/8" square smooth iron bars 2' long. Most of the bars will stay in place over time, but in swamps or other wet soils it is not uncommon for them to "walk out" over time.
Most bars pop up an inch or two in a cold winter, but will settle back during thaw.
It was really fun doing precision Monitoring in Toronto and observing 150 year old buildings pop up and down (very slightly - like 3mm) with the change in seasons and weather.
For a couple years in the mid-90's we had frost depth deeper than 7' in Hamilton. They had to steam-jet the water mains to open them up.
-Arie Lise O.L.S.
Though I don't have much frost here,I assume a monument should be on firm ground,and there should not be movement whatsoever,otherwise if there is a land slide,If the frost decay the things you establish,and move, good excuse for the client for relocation,(not seriously).
As I see the specifications you have mentioned will have to be varied according to terrain.
Like several others here I do not have a definite scientific answer. I like the Stefanos Beligiannis answer though.
I have seen frost heave myself in monuments so I don't think there is a lot of doubt that it exists. The amount a monument may move seems more dependent on factors like what the soil is composed of that surrounds the monument, the depth the monument is set, etc., etc. rather than exact movement based on temperature only.
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