ENGINEERING question , Concrete v Tarmac

[mercman24]

now that all of Pattaya and Jomtien is being dug up, with traffic mayhem everywhere, a question springs to mind, which is more cost effective as a road surface , concrete or tarmac, ? ok i know they are laying pipelines etc in some places, but Jomiten second road, this has been going on for ever, i remember back in the uk years ago they resurfaced 3  road in 3 days, using tarmac

[Crossy]

Concrete doesn't soften in the tropical heat.

 

Try riding your bike down the left hand lane of one of the tarmac highways...

 

[johng]

It seems to me that concrete stands up better to melting in the sun,flooding and overloaded trucks.

 

Tarmack is quick and a nice smooth quiet surface can be achieved.

 

Which is cheaper ?  id say concrete but have no idea.

[stubuzz]

Concrete is used on softer ground. 

[timendres]

5 minutes ago, johng said:

It seems to me that concrete stands up better to melting in the sun,flooding and overloaded trucks.

 

Tarmack is quick and a nice smooth quiet surface can be achieved.

 

Which is cheaper ?  id say concrete but have no idea.

I believe concrete is the more expensive build. And has higher repair costs. But lasts much longer.

Tarman is cheaper initially, and is cheaper and easier to repair, but has a much shorter life span.

In my state of Michigan, they allocate concrete vs. tarmac on a percentage basis, typically using concrete on the major highways, and tarmac elsewhere, but it is quite a political process.

[Surelynot]

Concrete, but being brittle it can only be used on very stable substrate. 

[Kwasaki]

3 hours ago, mercman24 said:

concrete or tarmac, ?

concrete

[jacko45k]

12 hours ago, Surelynot said:

Concrete, but being brittle it can only be used on very stable substrate. 

 

12 hours ago, stubuzz said:

Concrete is used on softer ground. 

So which is it?

[Chazar]

25 minutes ago, jacko45k said:

 

So which is it?

concrete  with plenty  of  steel  in

[Guderian]

17 hours ago, timendres said:

I believe concrete is the more expensive build. And has higher repair costs. But lasts much longer.

Tarman is cheaper initially, and is cheaper and easier to repair, but has a much shorter life span.

In my state of Michigan, they allocate concrete vs. tarmac on a percentage basis, typically using concrete on the major highways, and tarmac elsewhere, but it is quite a political process.

Yes, that's about my understanding of it. Removing and relaying a reinforced concrete surface is more time-consuming and expensive than asphalt or tarmac but it lasts longer. One downside to concrete is that it's impermeable, so in heavy rain it tends to build up standing water which can be dangerous. In the early days, the alternative surfaces weren't much better but 30 or so years ago they found out how to make a version of tarmac that allowed rainwater to drain very effectively through it and that's widely used in the UK now. I'm not aware of any new major roads that have a reinforced concrete surface.

 

From what I've seen over the years there's a major downside to using tarmac in Pattaya in that the contractors usually do a lousy job. Whether this is down to incompetence or cost-cutting I don't know, but they seem to make a much better job of laying a new concrete surface here. I was amazed to see how quickly the tarmac surface of the new Jomtien Second Road simply fell apart between the Machanu junction and Soi Rompho after they opened it around a decade ago, and indeed now it's all being replaced with reinforced concrete.

 

 

[johng]

1 minute ago, Guderian said:

I was amazed to see how quickly the tarmac surface of the new Jomtien Second Road simply fell apart between the Machanu junction and Soi Rompho after they opened it around a decade ago, and indeed now it's all being replaced with reinforced concrete.

That area floods frequently..now they are digging everything up you can see how thin the tarmac was on top of another thin layer of gravel and a thick layer of sand,in the heat the tarmac melts and overloaded trucks cause deep furrows,when it rains the sand washes away.

 

5 minutes ago, Guderian said:

One downside to concrete is that it's impermeable, so in heavy rain it tends to build up standing water which can be dangerous

Well why don't they slope (camber) the road and install drainage at the lower side of the slope like they do in "other countries" ?

[steve73]

My understanding is that concrete is liable to frost damage, whereas Tarmac can soften excessively in heat.

 

Hence why most new major roads in T/L that expect heavy traffic are using concrete...  Minor roads continue to use Tarmac due to cost, and often get damaged easily from heavy loads.

[petermik]

Do concrete roads lead to greater tyre wear?

[steve73]

1 minute ago, petermik said:

Do concrete roads lead to greater tyre wear?

I would suggest yes, since there is usually much more "road noise".... but then pot-holed tarmac is probably much worse for your tyres.

[Kerryd]

Drove along Highway 36 from Rayong yesterday and they are using reinforced concrete all the way where they are doing the expansion work.

I prefer the asphalt as a newly laid road is usually smoother and better traction. I've ridden along concrete roads that look so smooth they gleam and you can imagine that you won't have much traction at all on them, even in dry weather. Kind of like the surfaces at many PTT stations that you can nearly skate on. Almost dropped the bike a couple of times at PTT stations when I've put my rubber-soled boot down and it slid out like I was on ice !

One thing I think they (the government) looks at as well, is repairability. Most of the concrete roads (and bridges) are built in modular sections. That way, in the event of damage (from mortars/artillery/bombs for example) the damaged sections can be quickly removed and a new section put in place. With a trained crew, you could fix damaged sections within hours instead of days just by ripping out the damaged section, smoothing the underlay, then inserting a new (pre-fab) section of concrete. 

Yes, they can repair (small) holes in asphalt without all the big machinery. Small holes where they can bring in a small amount of pre-heated asphalt that they shovel into the hole then tamp down.
OK for small holes. Harder for big holes. Especially if you are anticipating heavy equipment to be rolling over it very soon. Much easier to rip out the damaged concrete section, smooth it down (even by hand using shovels/rakes) then insert a new pre-fab concrete slab.

And they can make asphalt very resistant to "melting" - if they wanted to. 

In Kandahar (on the airfield) we had dirt roads everywhere. Then they (NATO and the Americans) had most of the roads asphalted. I personally thought it was going to be a huge waste of time and money, expecting the roads to literally melt in the 50 degree Afghan sun.

But they didn't ! Even with Leopard Tanks and heavy tractor-trailer trucks and all manner of armoured vehicles rolling over them. We never even had the "grooves" where heavy trucks/equipment cause the asphalt to slowly subside, usually in the outside lanes, usually within a hundred meters of an intersection. (But to be fair, we didn't have the same volume of heavy equipment rolling over the roads for long periods of time or having to slow down and wait at intersections for long times as well.)

I was still quite surprised at how well the roads held up and then of course started to wonder why places like Thailand couldn't do the same.

As for cold weather - I think places like Canada use asphalt almost exclusively, even in really cold places. I can't recall off hand ever seeing a "concrete" road in Canada actually.

I think the biggest issues here are cost (contractors trying to maximize profits) and the competence of the companies doing the work (and probably all with zero to no oversight or quality control from the contracting authority).
 

[jacko45k]

17 minutes ago, Kerryd said:

I prefer the asphalt as a newly laid road is usually smoother and better traction. I've ridden along concrete roads that look so smooth they gleam

I have ridden the other end, turning off Sukhumvit Northbound into Hwy 36 and been concerned how shiny the new surface looked as I hit the bend on my bike. A sprinkle of rain on a greasy road may be a killer!

[GreasyFingers]

6 hours ago, Guderian said:

In the early days, the alternative surfaces weren't much better but 30 or so years ago they found out how to make a version of tarmac that allowed rainwater to drain very effectively through it and that's widely used in the UK now. I'm not aware of any new major roads that have a reinforced concrete surface.

I hope you are a very good engineer and if so will stand corrected.. The only problem with water on roads is when it enters the sub-grade. Originally it was bitumen 2 coat to disperse water away from the sub-grade. Hot mix (tarmac), is intended to do the same thing but last, maybe 10 years depending on thickness, longer than a bitumen seal.

Concrete has always been used on highways in Oz that were subject to flooding.

[digbeth]

When they widened the Hwy 7 from Chonburi to Pattaya almost 10 years ago (36/Regents School turnoff) the concrete was very rough, now that they have paved over the concrete with bitumen in sections it is smooth now.

 

Maybe tarmac alone won't survive Thai heavy trucks with thing falling out the back of them, and the yearly floods The roads that goes down south past Huahin seem to be full of potholes when it was just tarmac, most of it is now concrete 

[stouricks]

21 hours ago, johng said:

That area floods frequently..now they are digging everything up you can see how thin the tarmac was on top of another thin layer of gravel and a thick layer of sand,in the heat the tarmac melts and overloaded trucks cause deep furrows,when it rains the sand washes away.

 

Well why don't they slope (camber) the road and install drainage at the lower side of the slope like they do in "other countries" ?

That car is driving across the road, is the driver THai? 555

[johng]

49 minutes ago, stouricks said:

That car is driving across the road, is the driver THai? 555

Doing a 15 point turn ?