Consideration should be given to balancing backsite and foresite distances
> Consideration should be given to balancing backsite and foresite distances
The whole point of reciprocal leveling is to address severely unbalanced and unusually long sight distances. I wouldn't bother trying to balance the river distance with a landward distance, as that would needlessly introduce additional error.
Nevermind: I was thinking differential leveling. Brain Fart
Jon,
It is the bridge with the recently replaced span.
Josh
This is something I used to do for months at a time, we always calculated the C&R, we were often running 40 miles plus between bench loops and 3-5 miles trig level legs, you would be surprised at the accuracy obtained, for short legs like the one described there is probably a .04' adjustment for C&R I would calculate it, but you don't have to. It's a simple formula. I would want to see a +10.02' reciprocate with a -10.02'.
Let me know if you see a big difference in the existing control. Dirt is built using that
I did a site calibration using control on both sides for the causeway construction and didn't see any problems. Difference in dirt construction and concrete construction.
Better get something to set the legs on using an S6 on concrete. Mine always gets the shakes when set directly on concrete.
Jim is correct, applying C+R to either or both is a waste of effort.
Th C+R is canceled by doing reciprocal from both ends of the line.
I have not seen much difference in the project control. I ran through 4 project monuments on the east side. One monument was about 0.04' different in the z value.
I have only checked between 2 on the west side and found 0.10' in the z value. I need to back check a couple more stations.
Another firm set a couple of pairs and I suspect they popped them in with RTK. I found a small elevation difference between their elevations and the project control. To date I have not found any major problems and don't anticipate any issues matching it all up.
> Let me know if you see a big difference in the existing control. Dirt is built using that
>
> I did a site calibration using control on both sides for the causeway construction and didn't see any problems. Difference in dirt construction and concrete construction.
>
> Better get something to set the legs on using an S6 on concrete. Mine always gets the shakes when set directly on concrete.
Yes, That has happened to me several times especially when setting up on narrow walls around protruding reinforcing steel.