What is Blue Topping?

[iceberg210]

Sorry for my ignorance but I've never graded anything but gravel and crowned it so I was wondering what this blue topping thing is that I've heard on the forum and also in grader literature. Thanks for the help.

Erik

 

[ForsytheBros.]

Iceberg-

It has been my limited experience down south that "bluetops" (typical wood hub stake with blue "whiskers") are used for finished grade work during blading operations. Whiskers help operator "see" top of hub easier to get to final finished grade. I've noticed them on final lift of flex base prior to asphalt paving, although i'm sure lots of folks here use them for final dirtwork elevations, etc....

 

[RonG]

The blue tape just identifies the grade stake as one with the grade and offset on it.That is opposed to any other stakes that you might find beside the road marking the ends of utility crossings etc.The tape for water will also be blue but it will say water on it and it is usually wider tape as well.
The grade stakes often have other information on them such as station number etc.The grade you are given will be finish grade in the center of the road after paving so you will need the plans to figure out the cuts for the gutters after taking the crown into account and/or what subgrade will be before the roadbase taking into account each lift of gravel/process/asphalt depending on what the engineers designed the road for.
I had one engineering company that always tied a pink ribbon right under the blue ribbon for us so there was no doubt what the stake was there for or maybe it was there to mark out their territory like a dog and a fire hydrant.Ron G

 

[zhkent]

A contractor I worked for built some miles of road that we "blue topped".
Prior to "blue topping" the ditches and backslopes were cut to line and grade, and the road roughed in from the cut or fill stakes that were sat on the outer edges where the cut or fill started.
After the ditches and backslopes were finished, and the road graded pretty close we would blue top the road.
We would set center line of the road every 100 ft, sometimes 50 ft. with a transit.
At each of these points we would drive an oak hub to dirt grade.
We would then set a hub on the edges of the road, measuring the correct width from the centerline hub. The these hubs were hammered to grade.
The tops of the hubs are then painted blue, they are very hard to find if not painted because the color of wood and dirt matches sometimes.
Then myself, a blue top runner, and the best dog ever would go about putting all the hubs to grade by cutting over the top of the hub and cutting down to where you leave no dirt on top of the hub when you make a pass over it, without going to deep and pulling the hubs.
Martin, the dog, and I did something like 26 miles, 18 or 19 with a Cat 12F and the rest with a Cat 140G.

 

[surfer-joe]

zhkent is closest, so far. The original "blue-tops" were short stakes or pegs, and the tops were colored with blue chalk, something most young guys wouldn't know about. Paint, or spray paint didn't come in till the early seventies, maybe late sixties. The blue whiskers are a good improvement.

 

[RonG]

I am sure that everyone has a method that will work for them but it would be a handicap to have to work around a reference point in the same area that you are trying to grade,just something else to have to avoid.
I always had offsets (2' from face of curb is generally what works the best) on each side of the street and by pulling a line between the two stakes with grade marked on them you can measure your grade at centerline and gutter to check your work.
There will almost always be structures set to grade in the paved area that you have to work around and can use for reference but a good eye and if you are lucky another hand to pull your stations for you so you don't have to get off of the machine and maybe run the compactor/roller is what gets the work done on any of the jobs I have been tasked to do.
You can have the grade stakes set at any interval that you require to get the control that you need on your finished product.
I agree that my answer did not address the original posters question properly,thank you Surfer Joe.Ron G

 

[mtb345]

when i was in ga they say when a guy can blue top a road that ment he was the best around

 

[zhkent]

Surfer-joe,
Did they have something to set on the chalked peg to hammer on?
Seems like they would of needed something or the chalk wouldn't last when hammering the peg in hard material.
I'm mixed on the whiskers. A half tenth cut or so over the hub would tend to grab the whiskers and pull them.
We were doing these roads in the 1990's

Ron-G
These roads didn't have curbs. We didn't work around the hubs we went right over them. By using the shoulder hubs for grade and for the top of the shoulder slope it would leave a very uniform width road. The centerline hubs kept a constant crown also.

 

[RonG]

I do not doubt that it could produce a fine job but in all my years I have never seen it done that way that I knew of.It would be interesting to try it with someone who does it that way every day.I am too old to try anything like that on my own and give it good marks.LOL
In the area that I work money rules and when boxing out a new road the expectation is that the final box grade will be as close to box elevation as possible because somebody has to buy the roadbase material that goes under the pavement and gravel is cheaper than process stone which is cheaper than asphalt etc etc so if they bid a job to take what it calls for then that is what they expect to pay for.It feels good to finish a job and have the boss tell you that we were within a ton or so of the numbers he bid.Your first box grade can be a little low because all the mainline pipe work will generate material but the final box grade should be right on.
As I am seeing it my method of grade stakes and twine can be set once and I can tell right where I am on subsequent lifts by pulling between any two stations so no matter what is called for I can check my work such as a radius with an elevated center.Since I can see my grade on the grade stakes while I am grading I don't have to dismount from the dozer/grader very often to check because as you know you get an eye for these things after years of practice.
I have done large slab work with the same method but of course these days with a rotary beam we can all be heros)
This is an interesting discussion,I don't get around the country much to see other people work so I am somewhat sheltered I guess.
Thanks for the replies and insight.Ron G

 

[zhkent]

RonG,
Curb stakes and string line are the way we do streets here too, just like you explained. It's the only way to go.
The roads we blue topped were bid to be put to line and grade with no rock. After a stretch of road passed the county would gravel it.
These roads all had ditches on each side and culverts or bridges at stream crossings.
The roads averaged a foot and a half above ditch grade.
By digging the ditches we got the dirt for the road. After the ditches were finished the advantage of blue topping was being able to finish the whole road including the shoulders and not have to go back later to clean up.
We would pick up any excess dirt from finishing and haul on down to the next fill, leaving the ditches ready to seed and the surface ready for gravel.

If your cutting curb grade without a grade checker good job. That is not a piece of cake.

Haven't done any of those roads since 95. If you get out here in the land of oz. would be happy to show ya some of them.

 

[RonG]

Sure would love to come and give you a hand there.That is how we build and maintain gravel roads here too.We cut the ditches with a grader and roll it to the center on each side and use the windrows that we made to resurface the road with.Cutting to grade with the hubs in the roadway might be the best way after all is said and done considering man hours etc.
I like doing roadwork because as you say it is a fairly skilled operation and not every operator has the discipline to learn it properly but I have a good eye acquired probably from working alone so much but I hardly ever get off of the machine to check my grade as I am so confident in my ability.
I am now retired not of my own wishes but I am old and cynical and nobody wants to work with me so the skills acquired over the years are just going to waste.
One of the posters here just bought a Case 580 with low hours and lives in the next town to me so I showed him a little about the machine and now it looks like I will get to do some work for him later on.Glory be!!!Happy Days are here again.Ron G:notworthy

 

[Northart]

Blue Tops

In the old days ;

Blue tops, were Blue keel stone, or chalk on 1 1/2" square wooden pegs 6",8", 10" long. They were set in the sub base, with a bull ***** and sledge pounding a hole opening 1st. Then pounded in with a 4# hammer, to exact grade. Then Guard Stakes were put in alongside, to show location. This is where the "Stake Hopper" came into being.

Nowadays, they are set, painted blue and blue whiskers mounted on the edge, parallel to the travel direction, so the whiskers, don't bend over the top of the hub, get pinched and pulled out. They bend over in the crush alongside the hub.

Blue tops are for the finish course,(Crush aggregate/D-1) Asphalt goes on top. Blue whiskers used here.

Red Tops are for the sub base course, (-2", or whatever classified specs called for) Pink whiskers used here. Pink shows up better than red.

I carry a contrasting color, yellow whiskers usually, when one hub or whisker is pulled out, my stake hop, puts a yellow one back on, so the surveyor can verify it's accuracy later.

The hubs and whiskers come in varying lengths, depending upon material where used, and accuracy(weak shoulders) of previous lift, and thickness of lift desired.

Now with the new grader mounted, computer blade controls, it becomes another ball game. Less wood.

 

[Eric]

First construction job I had was hopping stakes for the finish blade hands. To me it was a little wood stake with blue whiskers. A "blue topper" is slang for finish blademan in my neck of the woods.

 

[pushkid84]

what we mean

any were i have worked worked blue toping means finshing your ab grade and you do have to be good on a blde to finish:drinkup

 

[637slayer]

i was cutting pinktops one time, wyo switched to pinktops in 02 and the boss sent the new girl laborer with me, about 20, about the finest body i have ever seen, always wore tight wranglers and small tshirts, it was on an interstate job so the other side had alot of live traffic, it must have been pretty impressive watching my operating skills cause cars would honk at me all day. it was a real treat for the bladehand he was older than me and she was all he could talk about, i think he was in love.

 

[Keres]

bluetops are the wooden hubs that you set at the grade of the rock. the asphalt or concrete goes on top. you need survey skills to set hubs. the idea is to express the grading plan so that the grader man can run over the tops of them and finish the road to plan. i work all day with that ****. i love the project i am on now cause it is about 5 miles of residential limestone road with a 65yo graderman who owns the paving company. the road is smooth like glass.

the trick to setting hubs is that you never want to make the hole too deep. the harder the rock the better. you want to use only a 12lb hammer. 10 is the min, but a 16 lb hammer will destroy your joints over time. 8 lb hammers just tear up the gad (or bull pin). the heavier the hammer, the easier it is to hit the target on center (strange but true). best hammer i ever used was called a 13lb... said 12 1/2 lbs on the stamp. long handle swinging overhand preferred, but the handle length is a separate topic.

1. get your position and paint a dot (RTK GPS or tape).
2. get your cut or fill on the rock (level, rotating laser, but i prefer a Trimble S-6) and mark the gad to grade.
3. set the gad by tapping it lightly into the rock. a few good firm taps to set it straight up and down... with practice you can do it with one hand.
4. standing at the hypotenuse to the gad, imagine a point in the middle of the gad and never take your eye off of it.
5. place the hammer on the head of the gad and gently flick the sledge behind and then above you. never let the hammer touch the rock.
6. while the hammer is directly above you (and you can feel it loose it's gravity) gently flick your wrists down while bending your knees. you want to keep your back as straight as possible. the idea is to let the hammer do the work and create the most amount of falling distance you can. this is not a muscle thing, it's a skill thing.
7. when the hammer bounces off the gad, use your wrists and flick it behind and up over you again, remember... don't let it touch the ground. as long as you use the energy from the bounce, it will come right back over your head naturally.
8. repeat this process until your mark is about 0.1 to 0.15 above where you need your hub to be... depending on the density of the rock. you never want to make the hole too deep, this is what causes hubs to settle downwards. one thing to know is that when you pound a gad into rock, the ground around WILL naturally raise up, sometimes as much as a tenth... so factor that in when you are estimating how deep your hole is.
9. now place your hub. the hole should be smaller and not as deep as the hub length. tap the hub down at first, then when it is set, you can use an overhand swing to knock it into place. it is not necessary to do it overhand, but when you get good at it you can do it to save time.
10. once the hub is close to where you need it, check the grade. if the hub is within 0.08' then you simply tap it down with baby taps to grade... each tap is about 0.005', depending on the density of the rock and the depth of the hole. you have to be careful not to mushroom the wood hub too much (mushrooming means that the hole you set was not deep enough and the hub is sticking up so high that the wood has become frayed and soft on the top of it). mushroomed hubs will loose grade... can be as much as 0.10'
11. when hub is on grade, tap in a chaser (feathers)using a claw hammer. paint it with whatever color. the color doesn't matter. what does matter is that it is straight, on grade and visible to the grading crew.
12. get your as-stake shot.
13. move on to the next hub.