As a person that rides motorcycle avidly I'm always distressed when the most important metric of a road gets a tiny mention, when discussing those new technologies.
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)
Because motorcycles are the number one users of road? Because the enjoyment of a small proportion of users outweigh whatever environmental and economic costs of improving infrastructure?
Motorcycles and bicycles have a vastly disproportionate impact on improving traffic flow. As traffic density increases, two wheelers fill the gaps left by cars, occupying effectively zero road space when traffic is completely gridlocked. Bikes also occupy very little parking space - five or six motorcycles can fit in the space of a single car.
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.
Even if all of this is true and then some, it doesn't change the fact that there are very little motorbikes on the road. Switching to these types of roads, even if it were impossible to ride on for motorbikes might still be a net positive for the environment.
Not really. In much of Asia, which is most of the world's population, two wheelers dominate. Traditionally bicycles, which was followed by motorbikes in South and Southeast Asia and electric scooters in China.
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.
> Because motorcycles are the number one users of road?
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.
Maybe they were just a terrible driver. I live in a cold U.S. State and have never slipped on Ice and RearEnded someone. I have never been in a situation where I slid down a hill and couldn't stop, mostly because I drive like you are supposed to in the Winter. Self driving cars will invalidate the need to worry about traction as they will force themselves to adjust to conditions instead of humans choosing to drive inappropriate for current weather conditions.
If everyone drove 1mph do you believe there would be as many car accidents from slipping? Nope. This type of event occurs because of human misjudgment.
Yes, and the world would also be a safer place if people went 0 miles per hour and never left their houses, but both situations are pointlessly unrealistic.
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.
I think you missed the point. I didn't give the 1mph example to imply that it should be the way it is. I used it to point that you are incorrect in saying "or maybe they were not." Accidents, mishaps, misjudgements, say what you will, but they are all just human error, not "acts of god." So you are incorrect to say they were anything but that, no matter how much you wish they were.
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.
It is a problem for cycles too - at least road bikes with thin tires.
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!
Well, comparing wet-weather conditions with theoretical max cornering speeds is ludicrous, quite frankly. Of course there's a reasonable change of slippage at 25kmh on racing slicks.
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 ;)
> Well, comparing wet-weather conditions with theoretical max cornering speeds is ludicrous, quite frankly.
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.
I see a bunch of people crabbing about motorcycles and how they shouldnt stop us from choosing a more slick road surface.
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.
People driving inappropriate for weather conditions should not be a factor in our decision making. If anything it just proves that we should work harder to stop drivers who are obviously incapable of determining appropriate driving procedures for current weather conditions. There will be the day when if you have a self driving car and you get in an accident with someone who is not in one, the manual driver will always receive the ticket. Just like in fender benders with the person who is in back.
I think certain plastics could be safer material since you won't need to paint them to mark lanes. You'd just bake in the colors while extruding. The only problem I see is can plastics maintain the required texture to ensure the best grip for all kinds of tires and conditions. I would like them to test this out before using it even as a replacement for sidewalks.
I think they would have paid attention to traction, bicycles are pretty popular in Rotterdam so I can't imagine them not having put much thought in to it.
Fortunately we don't optimize for minorities of recreational riders. If your motorcycle doesn't have enough traction - well it's an unsafe vehicle and you should have it fixed.
Motorcycle traction and car traction are not different things. And if roadways should be optimized only for non-recreational use I hope they work on banning car trips for leisure soon!
Yes they are two different things. Cars have 4 wheels and can make up for lost traction from other wheels. Motorcycles can't. They aren't being optimized for either of those conditions, they are being optimized based on environmental safety and necessity.
Note to marketing guys: find a better word than 'plastic'. You lose out because it sounds unenvironmental and is also associated with cheap, shoddy products. Go for something like 'polymer' instead.
If he did that it would diminish the clicks for people who can associate plastic with other items. I think very little people are associating polymer to their pop bottles.
Plastic in large quantities can become very, very expensive. It's cheap when you make a bottle or any kind of thin package, but as measured in kg, plastics are not cheap at all (but have interesting properties).
Other articles about this made it sound like they'd use re-used, granulated plastic, like that fished out of the ocean's 'plastic soups'. I don't know anything about plastic manufacturing or chemistry, but that was supposedly one of the big selling points - that the materials are cheap and needed to be disposed of anyway, some way.
Probably not. Endocrine disruptors in the environment can result from degradation of certain polymers, releasing chemicals such as bisphenol-A (BPA), phthalates and other compounds. For example, materials made with BPA such as polycarbonates, are associated with endocrine disruption hazards, particularly for children.
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.
Plastic is not a sustainable nor cost-effective material to build roads out of. I am a mechanical designer who designs with plastics daily. All plastic polymer chains break down over time and there is no getting around it. Light, thermal-variations, water-absorption, and mechanical stress can cause microscopic polymer chains to break and this weakens the plastic. If you have ever seen plastic that has become brittle with old age or sunlight you have seen a perfect example of polymer-chain damage in plastics. The rate of polymer chain breakage can be slowed down through various plastic formulations but it can't be stopped, especially in an outdoor environment where it is contending with wild temperature variations, water, oil, sunlight, and cars driving on it.
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 Propaganda-Elephant in the Room: there is no such thing as "recycling plastics" - but still the word "recycling" is commonly used, even if the described process very clearly is not about recycling. Obviously, this is a downcycling process which will lead to dissolved plastic in the food chain after a few decades, so this is far away from an ecologically sustainable or clean solution, that might be acceptable for our next generations, it is plain stupid.
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.
"It’s still an idea on paper at the moment; the next stage is to build it and test it in a laboratory to make sure it’s safe in wet and slippery conditions and so on"
So these are produced in large panels, which are laid on a compacted roadbed, or perhaps on concrete supports. The problem I see is that of the joints - as cars & trucks drive over them, they'll flex the plastic, causing loud "thump thump" noises.
What's wrong with asphalt? It can be easily recycled, it's an otherwise pretty useless component of crude oil of which we have plenty. It can be repaired with relative ease.
"...recycled plastic, which it said required less maintenance than asphalt and could withstand greater extremes of temperature– between -40C and 80C. Roads could be laid in a matter of weeks rather than months and last about three times as long, it claimed."
"...asphalt is responsible for 1.6m tons of CO2 emissions a year globally – 2% of all road transport emissions."
WRT the first quote the road business in the USA is extremely corrupt along the lines of cellphone battery life always being advertised as about 3 times reality, etc, so it would be assumed the claims are outright false and the maint cost will be higher and only last 1/3 the lifetime of asphalt. Its an interesting cultural problem that the claims might actually be true in that that country!
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...
I don't buy the marketing blurn. How are potholes going to be repaired?
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.
I think you're assuming it potholes in the same way as asphalt. Even if it did, it would be repaired most likely the same way potholes are repaired today, by infection new plastic into the hole and forming the previous layer to it, just like we do with asphalt today.
It's recycled plastic, so I doubt it. Plastic recycling is very expensive process, so very small percentage of currently produced plastic is recycled one.
Would potholes still exist? Water can't penetrate plastic and soften it's structure, and tires can't grip onto plastic and rip it up... so it seems like there wouldn't be that problem.
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)