Everyone knows that walking on soft sand is more difficult than walking on a hard sidewalk. By that same token, MIT scientists are now suggesting that if road surfaces were to be made stiffer, large trucks would use less fuel.

Asphalt may not seem particularly soft to us as we walk on it, but that’s only because we don’t weigh several thousand pounds. The heavy weight of a transport truck, on the other hand, causes the asphalt to deflect downwards slightly beneath each wheel.

As a result, the truck is perpetually in a state of trying to climb out of an ever-so-slight depression in the road. This means that it burns more fuel than it would otherwise, producing more carbon dioxide emissions in the process. According to MIT researchers Hessam Azarijafari, Jeremy Gregory and Randolph Kirchain, this problem could be alleviated if roads were made of stiffer materials.

These could include traditional asphalt, to which a small amount of relatively inexpensive synthetic fibers or carbon nanotubes were added – about 10 percent of the total mix would reportedly make a big difference. An alternative would be to use a larger grade of aggregate when mixing the asphalt, resulting in a finished product made up of more rock and less binder.

Based on the scientists’ calculations, if 10 percent of US road surfaces were annually made stiffer over the next 50 years, a total of 440 megatons of carbon dioxide-equivalent emissions would be avoided. Although that represents just 0.5 percent of total transportation-related emissions for the period, it’s still a significant figure.

https://newatlas.com/environment/stiffer-roads-trucks-fuel-savings/

PermeateFree said:

Everyone knows that walking on soft sand is more difficult than walking on a hard sidewalk. By that same token, MIT scientists are now suggesting that if road surfaces were to be made stiffer, large trucks would use less fuel.

Asphalt may not seem particularly soft to us as we walk on it, but that’s only because we don’t weigh several thousand pounds. The heavy weight of a transport truck, on the other hand, causes the asphalt to deflect downwards slightly beneath each wheel.

As a result, the truck is perpetually in a state of trying to climb out of an ever-so-slight depression in the road. This means that it burns more fuel than it would otherwise, producing more carbon dioxide emissions in the process. According to MIT researchers Hessam Azarijafari, Jeremy Gregory and Randolph Kirchain, this problem could be alleviated if roads were made of stiffer materials.

These could include traditional asphalt, to which a small amount of relatively inexpensive synthetic fibers or carbon nanotubes were added – about 10 percent of the total mix would reportedly make a big difference. An alternative would be to use a larger grade of aggregate when mixing the asphalt, resulting in a finished product made up of more rock and less binder.

Based on the scientists’ calculations, if 10 percent of US road surfaces were annually made stiffer over the next 50 years, a total of 440 megatons of carbon dioxide-equivalent emissions would be avoided. Although that represents just 0.5 percent of total transportation-related emissions for the period, it’s still a significant figure.

https://newatlas.com/environment/stiffer-roads-trucks-fuel-savings/

Provided that the stiffer road would produce a net gain for the environment.

We already have a solution: steel rails. Get more freight on railways, less on roads.

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Agree. But I love trains.

Tamb said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Agree. But I love trains.

TOOT!

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

There were some concrete roads in Oz & the USA. I wonder why more weren’t built.

Ideally if would be useful (perhaps) if we could use existing waste plastic broken down and then converted into some sort of spray that could be used on existing roads

Tamb said:

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

There were some concrete roads in Oz & the USA. I wonder why more weren’t built.

Expense perhaps and repair costs higher and possible much slower to build as well

Cymek said:

Tamb said:

The Rev Dodgson said:

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

There were some concrete roads in Oz & the USA. I wonder why more weren’t built.

Expense perhaps and repair costs higher and possible much slower to build as well

Sounds logical.

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

Concrete is cheaper than asphalt?

Tamb said:

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

There were some concrete roads in Oz & the USA. I wonder why more weren’t built.

There are still lots of concrete roads built in Oz.

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

How much co2 does concrete produce?
‘Clinker’ – the big polluter
It is the process of making “clinker” – the key constituent of cement – that emits the largest amount of CO2 in cement-making. In 2016, world cement production generated around 2.2 billion tonnes of CO2 – equivalent to 8% of the global total.

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

Thought it was more expensive.
Thats why they only concrete the roads in flood prone stretches?

PermeateFree said:

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

How much co2 does concrete produce?
‘Clinker’ – the big polluter
It is the process of making “clinker” – the key constituent of cement – that emits the largest amount of CO2 in cement-making. In 2016, world cement production generated around 2.2 billion tonnes of CO2 – equivalent to 8% of the global total.

The coalfired power station I worked at sold our ash to a concrete company.
A reduction of 40 percent of Portland cement in the concrete mix is usually feasible when replaced with a combination of pozzolanic materials. Pozzolans can be used to control setting, increase durability, reduce cost and reduce pollution without significantly reducing the final compressive strength or other performance characteristics.

Peak Warming Man said:

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

Thought it was more expensive.
Thats why they only concrete the roads in flood prone stretches?

Concrete is widely used outside urban areas.

Nosie is the main problem in urban areas.

The Rev Dodgson said:

Peak Warming Man said:

The Rev Dodgson said:

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

Thought it was more expensive.
Thats why they only concrete the roads in flood prone stretches?

Concrete is widely used outside urban areas.

Nosie is the main problem in urban areas.

Must be just where I live. Haven’t seen a concrete road for years.

Tamb said:

PermeateFree said:

The Rev Dodgson said:

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

How much co2 does concrete produce?
‘Clinker’ – the big polluter
It is the process of making “clinker” – the key constituent of cement – that emits the largest amount of CO2 in cement-making. In 2016, world cement production generated around 2.2 billion tonnes of CO2 – equivalent to 8% of the global total.

The coalfired power station I worked at sold our ash to a concrete company.
A reduction of 40 percent of Portland cement in the concrete mix is usually feasible when replaced with a combination of pozzolanic materials. Pozzolans can be used to control setting, increase durability, reduce cost and reduce pollution without significantly reducing the final compressive strength or other performance characteristics.

Yes, 30-40% fly ash (or other alternative materials) is common, and 70% or more quite feasible. You can also make concrete with no Portland cement at all.

Maybe use some kind of geoploymer. Doesn’t have to be hugely strong like concrete. If we could just make cheap large blocks of it using locally sourced aggregate and sand, they might end up harder than asphalt.

party_pants said:

Maybe use some kind of geoploymer. Doesn’t have to be hugely strong like concrete. If we could just make cheap large blocks of it using locally sourced aggregate and sand, they might end up harder than asphalt.

Stiff road paving does need to be strong, but geopolymer concrete can be made as strong as normal concrete, and has been used for airport runways in at least one project.

After water, concrete is the most widely used substance on the planet. But its benefits mask enormous dangers to the planet, to human health – and to culture itself.

In the time it takes you to read this sentence, the global building industry will have poured more than 19,000 bathtubs of concrete. By the time you are halfway through this article, the volume would fill the Albert Hall and spill out into Hyde Park. In a day it would be almost the size of China’s Three Gorges Dam.

After water, concrete is the most widely used substance on Earth. If the cement industry were a country, it would be the third largest carbon dioxide emitter in the world with up to 2.8bn tonnes, surpassed only by China and the US.

https://www.theguardian.com/cities/2019/feb/25/concrete-the-most-destructive-material-on-earth

————————————————————————————————————

Cement is the source of about 8% of the world’s carbon dioxide (CO2) emissions, according to think tank Chatham House.

If the cement industry were a country, it would be the third largest emitter in the world – behind China and the US. It contributes more CO2 than aviation fuel (2.5%) and is not far behind the global agriculture business (12%).

Cement industry leaders were in Poland for the UN’s climate change conference – COP24 – to discuss ways of meeting the requirements of the Paris Agreement on climate change. To do this, annual emissions from cement will need to fall by at least 16% by 2030.

https://www.bbc.com/news/science-environment-46455844

The Rev Dodgson said:

party_pants said:

Maybe use some kind of geoploymer. Doesn’t have to be hugely strong like concrete. If we could just make cheap large blocks of it using locally sourced aggregate and sand, they might end up harder than asphalt.

Stiff road paving does need to be strong, but geopolymer concrete can be made as strong as normal concrete, and has been used for airport runways in at least one project.

Yeah, that west of Brisbane airport is one I can think of, but can’t recall where it exactly. It was privately built IIRC. I wonder what the cost comparison is to regular concrete.

Low carbon cement revolution – the options now and the challenges still ahead.

he technological solutions are already available to make the move to low carbon cement for construction, according to University of Melbourne zero carbon researcher Michael Lord.

Sadly, he says there are still “huge institutional barriers” standing in the way of these low carbon options.

“We just need the incentives created to get there.”

He told The Fifth Estate that the big barrier is cost. Some commercially available low carbon alternatives remain around 10-15 per cent more expensive than the conventional version, even though there’s not always inherent reasons for the inflated prices.

The problem is that the demand just isn’t there. “These are still niche products.”

Another barrier is the legacy left by decades and centuries of using the standard Portland cement. Lord says there’s a perceived risk for taking on a novel material because of the potential of something going wrong.

https://www.thefifthestate.com.au/innovation/materials/low-carbon-cement-revolution-the-options-now-and-the-challenges-still-ahead/

Tamb said:

The Rev Dodgson said:

Peak Warming Man said:

Thought it was more expensive.
Thats why they only concrete the roads in flood prone stretches?

Concrete is widely used outside urban areas.

Nosie is the main problem in urban areas.

Must be just where I live. Haven’t seen a concrete road for years.

I think there is a section of concrete road as you come off the Western Ring Road out Bundoora way. Melbourne people? Is this right?

The Rev Dodgson said:

Peak Warming Man said:

The Rev Dodgson said:

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

Thought it was more expensive.
Thats why they only concrete the roads in flood prone stretches?

Concrete is widely used outside urban areas.

Nosie is the main problem in urban areas.

Concrete with an asphalt topping is the standard for freeways throughout eastern Australia now.
The concrete provides stiffness, reduces maintenance and gives good road mileage.
The asphalt topping reduces the road noise.

I wish all roads were made this way.
But occasionally they still make freeways away from urban populations out of continuous concrete with no topping – noisy and bumpy.
And for minor urban roads still use asphalt without concrete – high maintenance due to cracks and potholes.

Just a note here that concrete technology for roads has improved enormously in the last 40 years. The old ones with expansion joints and shrinkage cracks were awful for both performance and maintenance. And the next generation concrete, without expansion joints but with inadequate control of surface roughness, was good for maintenance but tended to shake vehicles to bits.

Peak Warming Man said:

The Rev Dodgson said:

party_pants said:

We already have a solution: steel rails. Get more freight on railways, less on roads.

Also much easier to convert to electricity, and feed braking energy back into the system.

And for the remaining vehicles on the road, switching to concrete would be stiffer at lower cost.

Thought it was more expensive.
Thats why they only concrete the roads in flood prone stretches?

The reason they concrete the floodways is because the bitumen becomes alluvial detritus as floods was the road surface away.