HGVs cause much of the wear and tear on roads, as well as making the road a more dangerous and hostile place for other users. There is much interest in removing them from the road network, especially congested local roads. We can do this by looking to neglected railways of the past.
A hybrid road/railway is built, with a single rail running down the centre of each lane. Special HGV trailers equipped with double flanged retractable steel wheels will be able to use this rail to support the bulk of their weight. As the rail will also guide them, and the rolling resistance will be significantly reduced from using steel-on-steel rather than rubber-on-asphalt, we will be able to connect these trailers in trains, making their transport even more efficient. At the end of the line, the trailers can be re-attached to the trucks and continue on their last mile journey. With the trailers connected in trains, we can move them significantly slower without increasing labour costs, as one driver may be hauling four or five loads instead of just one.
Given the simplicity of the system, it should be significantly cheaper to construct than a full railway, and due to the aforementioned advantages in efficiency, far less environmentally damaging than a full road would be. For a small additional expense, the lines could be electrified, further reducing their negative impacts.-- Selky, Apr 15 2024 Wiki Caillet Monorail https://en.wikipedi...ki/Caillet_monorail [Selky, Apr 15 2024] Wiki Addis Monorail https://en.wikipedi...Single_Rail_Tramway [Selky, Apr 15 2024] Wiki Ewing Monorail https://en.wikipedi...g/wiki/Ewing_System [Selky, Apr 15 2024] Wiki Road Rail Vehicle https://en.wikipedi...2%80%93rail_vehicleVehicles that can run on both roads and rails. [Selky, Apr 16 2024] Beats hell out of the HyperLoop. Maybe Mr. Mush will throw a couple billion in. He gets bored easily. Why not include the head ends of each trailer? You will need to power it, rails or not. Line 'em up on the rail and have the remote throttle/brake operated along with steering via the rail. On and off ramps for the monorail will be a problem, and merging at speed. But it will be cheaper than pure individual truck freight. It gives the drivers a chance to sleep.-- minoradjustments, Apr 16 2024 This is not a new idea or invention as helpfully pointed out by [Selky] in the links. I think it would count as "look at this cool 100 year old invention I found on Wikipedia, wouldn't it be great if it was used more than it currently is".-- pocmloc, Apr 16 2024 [pocmloc], the original monorail systems were not used for hybrid road-rail vehicles.-- Selky, Apr 16 2024 //the original monorail systems were not used for hybrid road-rail vehicles.// Yet the addis and ewing systems had a single rail, on which ran the main flanged wheels of the vehicle, and then one (Ewing) or two (Addis) sets of additional stabilising wheels which stopped the vehicle falling over, by the cunning principle of rolling on a hard surface (aka a "road") adjacent to yet offset some distance from the steel rail.
Your description is pretty much exactly the Addis system.-- pocmloc, Apr 16 2024 Lovely idea [+] needs work to make it so it can derail without causing harm, otherwise trucks who have to suddenly change lanes will crash. I disagree about HVGs making the road a more hostile place.-- Voice, Apr 16 2024 [Voice]; solved by making the rail "inside out" ie. a steel groove like a slot-car, flush with the road. Still use retractable load-bearing wheels, but with the flange in the middle. As a hybrid, it should keep the trucking lobby happy, while also having the efficiencies of rail. (I'm a fan of an old rule they used to have here, that trucks could only go short-haul, taking freight from the long-distance trains to the final destination. Lobbying killed it some decades ago, so we have trucks everywhere instead, being all loud & inefficient.)-- neutrinos_shadow, Apr 16 2024 [neutrino] You could achieve what you want by replacing all interstate highways with railway tracks. Then long-distance travel or freight and people would be done by super-efficient high-speed trains (i.e. more like Shinkansen than Amtrak) and at the terminals freight would be transferred to local delivery trucks and people would be transferred to local hire cars.-- hippo, Apr 17 2024 Rail is a lot harder and more expensive to retrofit than one would expect. Exceptionally short rail installations are forever being planned and never being implemented, even without the added complexity of replacing roads or residential areas.
Finally, industries have a bad habit of shipping toxic material on rail carriages, regardless of residential danger.-- 4and20, Apr 17 2024 random, halfbakery