Rotterdam to consider trialling plastic roads
theguardian.com
theguardian.com
Traction. If it's not at least as good as current best asphalt then don't bother.
Cities are already turning into motorcycle deathtraps, with all the "safety" nonsense generously painted everywhere (Which is slippery as hell, even during sunny weather)
Besides, if the road markings are anything to go by, it would be terribly slippery for drivers too.
Traction issues happen on all wheeled vehicles, motorcycles are just extremely sensitive to them. A few years back I got rear-ended (at low speed) because of pretty much the issue mentioned: fully painted crosswalk in wet conditions, the car behind just slipped on it and couldn't stop, ended up in the trunk.
We won't see a major population of self driving cars for decades. There are perhaps a dozen live models. We have millions of human driven cars now. This is the problem we solve for, not the ideal future fantasy.
We also solve for the future all the time, constantly, every day. We build solar powered devices to stop global warming and pollution. Every day we work towards a "future fantasy." It is like saying we don't need roads because we have these horses we have been riding. Why build rubber wheels when our wood carriages work just fine. Why build a smaller computer when this massive datacenter works just fine.
This wasn't winter, there was no ice, and it was low-speed urban driving. The wet crosswalk simply had close to no traction.
As pvdebbe points out, motorcycles can be extremely fuel efficient. A 125cc motorcycle or scooter can realistically achieve 90-100mpg. A small motorcycle is much more economical to manufacture than a small car, with about a fifth of the embodied energy. Modern bikes are equipped with catalytic converters and have sophisticated engine management, so produce very low levels of local air pollutants.
Two wheeled vehicles have an essential role to play in solving our current transport problems.
http://www.acem.eu/images/stories/doc/pressreleases/2011/PTW...
There's a reason why they continue to dominate, and it's not just the cost of cars (I've regularly seen people riding bicycles worth more than many people's cars here in China) - it's because they're practical! Parking, repair, exercise, lack of traffic congestion, etc.
I found these figures for road bike theoretical max cornering speeds - road bike with Continental GP4000 700x213c tires, rider weight of 180 lbs., tire pressure 105lbs, clean, dry, and smooth blacktop flat surface - not cambered.
Radius Speed
30 ft. 45.325mph
20 ft. 34.569mph
15 ft. 23.547mph
10 ft. 18.3675mph
However I've fallen off at under 15mph when taking a bend in the rain - very big difference from 45mph!It should be noted that it's also Rotterdam, the Netherlands we're talking about here. That doesn't mean that bureaucrats can't screw up, but if this type of road is unfit for bicycles they'll probably find out quick enough ;)
Depending on the exact paint (I guess since I haven't had this issue over all markings) fully painted surface can be (much) worse than wet-weather for loss of traction, and those can also get wet making any corner taken beyond walking speed a mortal danger.
Grip in cold conditions is important, and there are also interesting tradeoffs between noise, tire wear, and traction.
A slicker road surface is not a good idea in many places, see something like https://www.youtube.com/watch?v=Wp2sqrfGSPI where cars are slipping and sliding down a hill covered in ice.
Generally food and beverage containers are made from polyethylene or polypropylene because these plastics are very inert. They aren't made with compounds associated with endocrine disruption.
Since the proposed roadways were going to use recycled polyethylene pop bottles it shouldn't be a problem. However I'm skeptical about the idea on other grounds, I have real doubts about factors like durability and cost.
The road will be exposed to heat and sunlight both of which promote leaching.
So yes, lets make a road out of plastic, even though plastic is at it's absolute worst under the stresses roads undergo. I will join the "when will the road break" betting pool at 8 years and 2 months after the road is laid.
The solution is to reglement plastic production to a set of about max. 50 different recipes for different applications that actually can be recycled. Today we have thousands of patent-protected artificial substances called "plastic" and the plastics lobby is extremely strong in suppressing any discussion that goes into that direction.
EOT
"...asphalt is responsible for 1.6m tons of CO2 emissions a year globally – 2% of all road transport emissions."
WRT the second quote, that doesn't answer the question. If you can't mix the heavy stuff from the distillation column with gravel and pave roads with it, you'll have to ... crickets ... Bonfire it? Dump it in the ocean? Pour it in a pit and leave the cleanup to someone else? Ship it far away for someone else to use it as asphalt?
Damaged roads are very expensive ecologically. Saving the planet $5 on pavement is a good way to charge the planet $1000s in tie rods and suspension components, but out of sight, out of mind...
As for asphalt's CO2 footprint, that's the figure for asphalt mixed with cement. Extracting asphalt and bitumens from crude oil is literally the bottom of barrel.
Pardon typos, fat sausages on moving bus.