America's Biggest Asphalt Plant Is Shutting | Hacker News Reader

America's Biggest Asphalt Plant Is Shutting

bloomberg.com

65 pointshourislate39 comments

> The U.S. would need 63 percent more asphalt than its consumes now just to pave roads at the rate it reached a decade ago

Interesting how the article fails to mention that asphalt isn't the only way to build roads. Unless you live in an area with a lot of snow and rain, concrete roads are a better economical and ecological choice [1]. I'd prefer a limestone based road vs a petroleum based road if I wasn't living in area with frequent rain. Concrete is also lighter in color which makes it retain less of the sun heat, it's more pleasant to walk near it.

> with demand for construction materials in Texas rising 30 to 40 percent

Interesting fact to mention, except "construction materials" != asphalt. In fact, many road in Texas are already concrete based (which should make northern states sympathize more with Texas when they freak out over 0.5 inch of snow) and recent city road projects favor replacing asphalt with concrete [2]

Finally, people have seen what recent innovation in concrete pavements can bring, with this permeable concrete that instantly absorbs thousands of gallon of water [3].

[1] http://www.brighthubengineering.com/concrete-technology/4585...

[2] https://blog.cstx.gov/2017/02/01/concrete-streets-will-save-...

[3] http://www.tarmac.com/solutions/readymix/topmix-permeable/

Before I had moved to the US five years ago I had never experienced concrete roads. Now that I have, they are easily the worst experience. They might work in some areas such as the south. But on the west coast they are cracked, potholed, sections lifted out of alignment, they are rough and loud, and the markings are often worn down to the point of being nearly invisible (not to mention white markings on white concrete is always invisible in the rain, and given they never replace the reflectors that come off after a year you just have to guess you're staying in your lane).

From driving around Texas which uses concrete for a lot of highway development, I can tell you the exaggerated road noise doesn't help.

Agreed. The worst are the sectioned ones that ThumpThumpThump at about 20-50 cycles for miles. They collect rain in between sections and are more slippery, and less visible. Additionally, If you live where there is ice/snow, the road never heats from the sun and ices worse. I would love more asphalt roads, much easier and cheaper to patch, and maintain in non ideal situations, which is most roads.

It really stinks living on one of these stretches of roads, since you get to sit in your house and hear that thumping all day and night. That 40-45 mph range is where it starts getting loud.

I would love more asphalt roads, much easier and cheaper to patch

Concrete roads tend to be cheaper over the long term, as they require less maintenance. In some regions the difference can be significant depending on traffic volumes and climate.

This seems odd to me, living in Australia where alot of roads are asphalt I don't know how it would be cheaper to repair them like they do out here.

The just have a truck roll around and dump some more asphalt in the holes, tap it with the shovel and it usually fixes it up fine. If not they come around 6/12 months later and do it again.

With concrete, can you just drive by and drop some cement in the cracks and holes and move on? Don't you have to usually cut out parts, repave and block off the road for an amount of time?

It's the maintenance costs over time that are generally better. Asphalt is convenience in that it's much more of a patch job, but over time it tends to require more maintenance so the costs level out. Asphalt overlay atop concrete will generally result in a more long-term solution with an easily maintainable surface to avoid the noise complaints some have echoed.

As far as potholes go, my experience has been more the opposite, at least on local roads. I've lived in neighborhoods with both asphalt and concrete roads, both with infrequent maintenance from stingy local governments, and the concrete ones fared much better. Some of them had gotten basically no maintenance in 20 years and were still largely fine (the curbs being in worse shape than the road surface). But the asphalt roads without recent maintenance had giant potholes everywhere, and masses of disintegrating asphalt rubble at every place where they had a seam with a driveway / rail crossing / etc. It's hard to exactly compare like for like since I've only lived in a handful of places, and they differed in other ways too, but my impression has been that asphalt roads need much more frequent maintenance to keep from falling apart, and fare worse when that maintenance doesn't happen.

> on the west coast they are cracked, potholed, sections lifted out of alignment, they are rough and loud, and the markings are often worn down to the point of being nearly invisible

I'm not sure that is exclusive to concrete. In the northeast coast our asphalt roads have all the same problems except the "lifted out of alignment" and noise).

Right now since it is snow season I have to constantly look out for foot deep potholes that will destroy an axle.

Concrete is great if you dig it really deep and thick and have great drainage.

Around here (NY) they don't do any new construction with concrete surface, sometimes they pour concrete in sections and surface it with asphalt. Asphalt is the superior coating, bar none.

I agree they are terrible. Often sounds and feels like driving with a somewhat flat tyre.

I vastly prefer concrete, especially on the expressway, even up here in Chicago. The road isn't as smooth but... that's because it's usually ten or twenty years older than our most beat up asphalt roads. One of our expressways up here, I-355, used to be concrete, and sure, it wasn't as smooth, it was noisier. But there was never construction on it, because the road really never required heavy maintenance.

Since they replaced large sections of it with asphalt, it's under construction every single year.

I think that's more a result of poor construction (i.e. the effect of the cheapest bid).

Back in 1992 I drove on some (formerly) East German autobahn that had not been touched since the end of WWII. Our speed was limited to about 45 MPH due to the state of disrepair, but jeeze, it was 50 years old!

Making concrete takes a lot of energy.

http://www.eia.gov/todayinenergy/detail.php?id=11911

Making concrete doesn't take that much energy. It's around 130 kWh/tonne[1]. That isn't really all that much: compare to the 280-350kWh it takes to produce a single barrel of crude from the Alberta tar sands[2]. And that energy is increasingly coming from renewable sources, like wind and solar.

That said, Asphalt is probably one of the better uses for crude oil. Sticking it semi-permanently to the ground has got to be better than burning it and releasing all it's carbon into the atmosphere.

[1] http://www.sustainableconcrete.org.uk/energy_efficiency.aspx [2] https://en.wikipedia.org/wiki/Oil_sands#Input_energy

Carbon doesn't exclusively define pollution.

The problem with concrete is that they cook it with nasty stuff like coal ash. Plants spew all sorts of particulate pollution and mercury. Plus they frequently pollute water sources with stuff like sulfuric acid.

The use of coal ash ("fly ash") in concrete is generally considered a good thing.

It's making use of a waste product (from coal power plants) that otherwise gets dumped into the environment where it can pollute soil and waterways.

Unless you're downwind.

> That isn't really all that much: compare to the 280-350kWh it takes to produce a single barrel of crude from the Alberta tar sands[2].

The "tar sands" are a naturally-occurring asphalt deposit. To make asphalt cement out of it basically just requires digging it up and separating the sand from the bitumen. That's a very small part of the energy required to make synthetic crude.

noise, noise, noise.

It can be unbearable.

I have a Tesla, and driving on concrete freeways is so loud it's like I wasted my money on this quiet car.

There are some sections of Autobahn built with concrete slabs and they are terrible, even if it were for the noise alone [1]. But they are also problematic when it gets hot -- warped slabs and slabs being lifted into the air by pressure (since the slabs expand) happen regularly. And they are also problematic when it's wet. In other words, they're always problematic.

Concrete Autobahn is mostly replaced with proper asphalt Autobahn when a section is renewed.

[1] Since it's Autobahn many people don't drive a cosy 140 km/h (85 mph) but rather 160-250 km/h (100-160 mph) [and when the road is free 300 km/h, 190 mph, are observed regularly] so I assume the noise is worse on the Autobahn than on concrete highway.

> Finally, people have seen what recent innovation in concrete pavements can bring, with this permeable concrete that instantly absorbs thousands of gallon of water [3].

While certainly impressive, this leaves the question: Where the f..k is all that water going?

Typically, at least in cities here, the water goes off into drains, and then into a water treatment plant which prevents nasty stuff like oil or other car-originated toxins from compromising the ground below.

Something like this system, if not connected to drainage piping, would basically let all the liquid waste seep into the ground - compared to a sealed asphalt/concrete ground, where firefighters can spread sand or other oil binders to prevent widespread release into the environment.

The northern expressway in south Australia uses something similar made from bitumen.

Basically they lay a regular layer of non-porous bitumen, with side drains etc and appropriate camber.

They then lay the porous bitumen layer over the top. It's like a griller drip tray, without the delicious pork chops.

Concrete roads suck in areas with lot of rain of minor flooding.

>> Interesting fact to mention, except "construction materials" != asphalt.

Asphalt shingles are building materials, and it is definitely true that demand for construction materials in Texas is rising. Texas has a few shingle plants, and there are others in nearby states.

So we might say that "construction materials" != road building materials (though Texas is always in the process of building roads), and also that "asphalt demand" isn't entirely dependent on road building.

I'm very dubious about the first source you posted. It claims vehicles consume 15-20% less fuel when travelling on concrete compared to asphalt. That statistic doesn't pass a basic sniff test in my opinion.

I'm only moderately surprised that no one has informed our President so he can "fix this" :-)

That said, the history of this stuff [1] is pretty interesting as well. There were some 'test roads' in the desert outside of Las Vegas were the Dept of Transportation was trying different formulations for hot environments. In the desert the heat would make the roads more malleable than you wanted and trucks driving on them would leave some pretty impressive ruts. Concrete was used as well but the expansion and shrinking would destroy it too. Then there were some cobblestone roads that had been built in the 1800s that were still in good shape but you can't really make a freeway out of cobblestone :-).

[1] The History of Asphalt -- http://www.asphaltpavement.org/index.php?option=com_content&...

That makes sense. Asphalt is best made from heavy crude oil, and there's more of that in the US West and Canada. Importing heavy crude oil to the US is inefficient.

Asphalt is a by-product of refining crude oil into gasoline and heating oil. It comes from the left-over heavy bottom fractions, the really long hydrocarbon chains. Nobody buys crude oil just to make asphalt.

Since moving to Thailand I've come to despise concrete roads.

The Thai approach to road building seems to be: 1. dump/spread/compress boat loads of sand (yes you read that right, SAND) until you have a smooth surface that would work well for a kids sandpit.

2. Pour reinforced concrete slabs about 20cm/8" thick.

3. Wait for the inevitably overloaded trucks to destroy the surface.

I haven't seen a new asphalt road laid here yet, just re-surfacing so I'm not sure what their prep is like for that but the eventual result from abuse by pickups overloaded with watermelons/etc is less dangerous:

Asphalt tends to deform but keep a sold surface: the wheel tracks will be depressed, and the space between will become slightly raised (think like wheel tracks in the mud) but it can generally be navigated with care.

Concrete doesn't fail that way. It just cracks, the underlying sand gets washed away, and you have the wonderful experience of broken concrete with sharp metal sticking out the broken edges.

It doesn't help that Thai builders/society is obsessed with making things out of concrete.

Interesting. I seem to recall that when I lived in Malaysia many decades ago, someone told me that when they laid down the gravel and tar mix for the roads over there, they added a fair bit of rubber sap into it as well. Don't know if it was an urban myth, but the person who told me mentioned that the roads tended to react better to things like heat expansion from the sun's heat and vibration because the final compound was a lot more elastic. He also said that the added rubber provided extra traction for vehicle tyres.

Given that rubber is a massive raw produce of Malaysia, I could see that they could do this, but always wondered if it was viable from an engineering standpoint. I mean, the tar/gravel slush mix is quite hot, and I would have thought that raw, unprocessed rubber sap my break down in the mix?

Honestly I'm not sure. Rubber is produced here too, so its possible.

http://www.calrecycle.ca.gov/tires/RAC/

"Rubberized Asphalt Concrete". You're reusing discarded tires (which are extremely painful to recycle) and extending the lifespan of the road.

Not quite sure if the material in tires is actually rubber or some synthetic petroleum product, but I think the principle is the same.

> dump/spread/compress boat loads of sand

Could it be mechanically-stabilised earth [1]? That stuff underlies much of America's interstate system. It's resilient when done right.

[1] https://en.m.wikipedia.org/wiki/Mechanically_stabilized_eart...

I doubt it. It is possible but I doubt it.

Modern asphalt road maintenance can include thin overlays to extend the life of the roads instead of replacement or thick overlays, as low as 1/2" compared to the traditional 2". This overlay is made of some new material but also quite a bit of recycled asphalt pavement.

These may be combining to keep the demand for new asphalt lower despite continued demand for asphalt roads.

Bad idea. Some contractors do that. Now they do the same maintainance every year, as the thin asphalt doesn't last long.

It's a lot better to properly re-surface asphalt once every 10-15 years with a thicker layer.

Just throwing around words like green, recycled asphalt, etc doesn't mean it's a good idea, often it's a rip off, the we have to pay via tax.

> thin asphalt doesn't last long

Do you have a source for a "thicker layer" of asphalt lasting 10 to 15 times longer than "thin asphalt"? What is the cost difference?

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