Pavement Creep, and PK nail moving

Disturbed monument is rehabilitated. Now it’s all yours.  

Nate,

When I worked for a large highway construction firm back in the '80s I saw many examples of what you're talking about.  It can be eye-opening.  It's also a great topic with which to "dive" into spirited discussions with other surveyors and engineers.

My question is, simply put:  If you cut an X in each end of a mile of continuous concrete pavement on a day when it's 30° F, is it reasonable to think that the distance between them might be different at 100° F? 

There is a good argument to be made that the PCC pavement construction practices concerning expansion joints and materials would negate any appreciable "movement" of the pavement.  I am not a great scientist, but I have looked at many, many cases like this.  And my conclusion is that things move a great deal more than we think.  But I've also found there is a bid difference between actual "movement" as opposed to "deformation".  What I'm saying is pavements expand, but they also contract.  Two points might be a tenth or so further apart at 100°, but that difference might not be noticeable when observed at a cooler temp.  An although concrete can be very stubborn and remain pretty much where you placed it, it can shift or slide depending on the great number of forces to which it's exposed.

And then there is ACC (asphalt pavement)...

It's a whole different ball of wax, literally.  By design asphalt pavement is not rigid.  It "mushes" around a great deal given enough time.  Think of it like putting mag-nails in a bunch of jello...

It's a good discussion.  I'd like to hear if others have had similar experiences.    

One more reason to not rely on MAG nails, especially those hammered into asphalt, for control in the medium to long term. 

Subsidence?

One more reason to not rely on MAG nails, especially those hammered into asphalt, for control in the medium to long term. 

Exactly. Of course even the most substantial monuments can move, but we can almost always do better than relying on a couple of inches of asphalt to be stable. 

@paden-cash I do deformation surveys on long lock walls, some are thousands of feet long. The unconstrained ends move centimeters with temperature changes. That is why my reports show only movement perpendicular to the wall, which is what they are worried about

I experienced this recently as well. The MAG had crept about a tenth or so downhill from where it had been set ~7 years ago. 

In the northern Kentucky region, it has been standard practice in new subdivisions to make curb cuts on property lines and notches in centerline if concrete and Mag nails if asphalt.  If the centerline notch crosses the gap in between two concrete sections, in a few years, the notch will no longer line up.  Streets move quite a bit.  My old boss lived directly at the bottom of a cul-de-sac and the street literally pushed his garage off his house.  You could put your hand through the brick.

Does that mean if the front of the properties were never pinned, that the property line travels with the curb cuts?

Placing any mark in any pavement fits the definition of insanity. It's unsafe, impractical and temporary. It should be illegal. Witness corners are the solution. Just because you can do something isn't reason for doing it. 

Won't all of the monuments move over time with the new 2022 datum?

Here is a pic of a pipe, by a black gum. the black gum apparently grew, and displaced the pipe to the north. I set the REBAR that the GPS is on, knowing it is MORE like the original position. There were also signs of a DOZER having turned around there, and "Helping" the monument move.

It's not a pavement one, but there are things that displace monuments.

Nate

Did any of the adjoining deeds, that may have been surveyed in the intervening time, make reference to the pipe as the corner, if it had slowly moved over time?

Won't all of the monuments move over time with the new 2022 datum?

Sort of. Everything was already moving in the first place, but the reference frame is plate-fixed (so was NAD83), so monuments will "move with" the plate, and in areas where there is minimal local movement, coordinates will generally remain stable.

It's more accurate to say that reference epochs will be published more often in NATRF2022 than in NAD83, and that NGS-generated solutions will contain the instantaneous position (at time of observation) as well as the current reference epoch position. So, local and intraframe movement will be captured in those positions as well.

I did a survey back 15 yrs ago. Tied a PK nail in asphalt.

I tied it again last week. It had moved 0.30'.

Did the coordinate value simply change due to realization/control changes?

Or did the nail actually move in relation to other monumentation?

Then there is the case, such as former poster Paul Cook's house, where everything is sliding downhill.  Of course, that was in California where anything can happen.  It seems like his movement was on the order of four inches per year.

Won't all of the monuments move over time with the new 2022 datum?

Here we are talking about movement relative to other nearby monuments. The planned recalculation of the NATRF coordinates will be relative to tectonic shifts of continental plates,  etc.  

@tom-bushelman 

I would say no, disturbed monuments (curb-cuts) are just like a rebar/cap lying on the ground near a corner location, great to have found it but it's no longer valid.

Syntax is important, keep the words monument and corner separate.

It's best if the monument occupies the corner's position (or as a witness/reference monument such as a curb-cut), but as it moves because of local conditions the corner doesn't move with it.

The corner stays fixed in space where it was originally established with a whole bunch of exceptions of course. 

Does that mean if the front of the properties were never pinned, that the property line travels with the curb cuts?

We probably need to drive anchor sleeved rods...

https://www.ngs.noaa.gov/PUBS_LIB/GeodeticBMs/

That said, I have visited a 100 year old X cut in concrete that was within 0.05' in relation to other monuments in the area. 

We probably need to drive anchor sleeved rods...

https://www.ngs.noaa.gov/PUBS_LIB/GeodeticBMs/

That said, I have visited a 100 year old X cut in concrete that was within 0.05' in relation to other monuments in the area. 

There's a corner not far from here that is marked with a flagged 60d nail.  It lies about 4' off the edge of an old gravel road.  I set that corner in 1979 with no particular thoughts given as to its longevity.  But there it is.  The road was merely dirt then (actually graded sandstone in spots).  It's gravel now and the motor patrol whizzes by there occasionally.  The nail is just far enough off the road to avoid the patrol's ravages. 

Go figure.  I guess it's really a crap-shoot whether a monument sticks around or not, despite our best efforts.  😉