Any paving contractors out there? Need some advice

[Buppies]

The thickness of asphalt has nothing to do with how long it will last the base is what's all important(stone).

Several commentors here know what they are talking about. Asphalt should be laid in place depending on type (base mix BM25 or topping SM9.5A) at mix temperature 275 degrees up to 350 degrees. Maximum compaction takes place before 175 degrees. A one ton roller given enough passes will obtain proper compaction (normally 92% on nuclear gauge). A three to five ton roller will achieve compaction faster anything larger will be too large for driveway

If asphalt is laid and rolled to quickly the mat will split leading to premature failure. The seams of the different mats should be looped correctly so as to not leave large stone (segration) which leaves voids leading to premature failure. The trucks should also be loaded in a proper sequence to prevent segration

The depth of stone is determined by geotechnical tests and should be below the freeze line. Stone base is most important asphalt is only a running surface and has no structural integrity by itself

The stone base should be compacted to 95% on the nuclear gauge more than that will lead to failure down the road since once you go over 100% the base begins to degrade

As I am not in your area cannot really comment on costs as they can very greatly from region to region

If your individual use is residential and not big trucks then 2in of compacted asphalt is sufficient. Remember stone base and properly compacted is your friend and is where your money should be spent. If larger trucks dump and up 3in of base mix asphalt then 2in of topping

Hopefully this information is helpful

 

[roadhunter]

You don't have frost down there. It can move rocks and culverts like you wouldn't believe!

This ^^^^^. You beat me to it.

 

[paulharvey]

It's all about the base, all about the base, no tremble!

Seriously, if you have a good base, compacted, at least 6" thick, without gumbo underneath, and swales deep enough to keep the base dry, 1.5" of asphalt will last a long time.

I did a quick search for different areas regulations;
in Marion County fl, 1.5" asphalt on 6" base; ok, no freezing
Ohio DOT; 2" 'type 404' asphalt on 6" of '411 or 304 aggregate'; can't say they don't design for freeze...

Edit: I have attached a quick sketch of a cross section of a road or driveway. It shows (I hope) 2% crowned road using 1.5" of Sp-9.5, 6" thick of limerock extending 6" beyond your asphalt. A grassed shoulder along the side, and a meaningful swale. Ours always called for a 4:1 front slope, for 4 ft; in addition to a 4 ft wide, 6% sloped "stabilized" shoulder.

It's sketched fast, free hand, in the dark, with only 2 cups of coffee in me...

 

[vtsnowedin]

It's all about the base, all about the base, no tremble!

Seriously, if you have a good base, compacted, at least 6" thick, without gumbo underneath, and swales deep enough to keep the base dry, 1.5" of asphalt will last a long time.

I did a quick search for different areas regulations;
in Marion County fl, 1.5" asphalt on 6" base; ok, no freezing
Ohio DOT; 2" 'type 404' asphalt on 6" of '411 or 304 aggregate'; can't say they don't design for freeze...

Edit: I have attached a quick sketch of a cross section of a road or driveway. It shows (I hope) 2% crowned road using 1.5" of Sp-9.5, 6" thick of limerock extending 6" beyond your asphalt. A grassed shoulder along the side, and a meaningful swale. Ours always called for a 4:1 front slope, for 4 ft; in addition to a 4 ft wide, 6% sloped "stabilized" shoulder.

It's sketched fast, free hand, in the dark, with only 2 cups of coffee in me...

On my third cup. Base is important but the OP said he had good solid base so I didn't question it. Actually a durable paving job comes from the sum total of all the construction details. Drainage, depth of base, gradation of the base material, soundness of the rocks in the base and in the mix (LA wear). Compaction of base and mix, fine grading of the base, mix design and aggregate size, delivery temp of mix. paver design and capabilities,screed temp, crew skill and workmanship, roller size and operation, tack coats between courses, weather during placement etc. etc. Neglect or fail on any level and no amount of super mix placed on top will hold up.

 

[paulharvey]

On my third cup. Base is important but the OP said he had good solid base so I didn't question it. Actually a durable paving job comes from the sum total of all the construction details. Drainage, depth of base, gradation of the base material, soundness of the rocks in the base and in the mix (LA wear). Compaction of base and mix, fine grading of the base, mix design and aggregate size, delivery temp of mix. paver design and capabilities,screed temp, crew skill and workmanship, roller size and operation, tack coats between courses, weather during placement etc. etc. Neglect or fail on any level and no amount of super mix placed on top will hold up.

I agree. We don't use a hard rock base around here, but we don't have hard rock around either.

The asphalt used by driveway guys is often inferior to what would be used on a real road too. There is a fairly major contractor in Soundguy's area (hopefully not the company he works for) that was trying to sell 100% recycled asphalt to the country while I worked for the county. I don't mean 100% RAP as aggregate with some fresh AC added in; I mean 100% recycle, RAP and some chipped shingles; that's it..... they heated it to around 450, and supposedly remelted the AC in the RAP...

There's a ton of ways to go wrong paving; temperate, mix, density, paving in the rain... ect; but in general I think people focus on a single simple concept;1" vs 2" vs. 3" vs. more; when an asphalt drive or road is a total package/system. Any weak link in that system will reflect in the finished package.

Concrete isn't any better, 4" of 3000 psi concrete on a well compacted subgrade will outperform 6" on crap muck or gumbo.

I'm not so much questioning the OP's base, but often people think they have way more then they really do. 6" of base is ~600 lbs/Sq yard, and that's a lot of truck loads. I've seen a lot of people who say they have really thick base, they dumped "2 whole dump truck loads"... when you figure it up they might have 3"...

 

[paulharvey]

I do have a road question for those of you in the artic north (anywhere north of I-10 to me); will well drained base freeze? I assume it would have to have a high moisture content to freeze, but maybe I'm wrong.

I did live in WVa when I was young, but I didn't pay any attention to road buildinh when I was 10 or 12....

 

[vtsnowedin]

I do have a road question for those of you in the artic north (anywhere north of I-10 to me); will well drained base freeze? I assume it would have to have a high moisture content to freeze, but maybe I'm wrong.

I did live in WVa when I was young, but I didn't pay any attention to road buildinh when I was 10 or 12....

Well yes it freezes of course but because it is dry there is no water in it that expands on freezing to change the size and shape of it. It maybe a little damp of course but as long as there are open air filled pores between sand grains that moisture can expand into as it freezes it is stable.

 

[Soundguy]

Frost heaving bites..

 

[Soundguy]

I do have a road question for those of you in the artic north (anywhere north of I-10 to me); will well drained base freeze? I assume it would have to have a high moisture content to freeze, but maybe I'm wrong.

I did live in WVa when I was young, but I didn't pay any attention to road buildinh when I was 10 or 12....

They have heaving, we have perched water tables and expanding clay.

Can't win.

But yeah.. it's all in the stabilised subgrade

 

[jmc]

A little off topic, sorry, but are paving prices down due to lower oil prices? I've got a big job that needs it, at some time.