Rail transportation, train weight to passenger weight, reduce how much?

In summary: The passenger train was designed to be lightweight, but it still weighs 380,000 lbs. with 512 seats. This is 9 times the weight of the passengers. The locomotive weighs about 10% of the maximum train weight it will pull, but the rail cars are still built to be heavy. ICE 3 is an example of a train that uses multiple cars to spread the weight, but it still weighs 1,000 lbs. per seat.
  • #1
Spinnor
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If travelers sat on connected lawn chairs on wheels guided by rails pulled by a motor on wheels we might reduce the ratio of rail train weight to that of the weight of passengers carried.

An Amtrak passenger train weighs about 200,000 lbs. and holds say 100, 200 lb. people, for a ratio of about 10 to 1.

A light weight auto is about 2000lbs. and can hold five passengers for about 1000lbs. (those are likely crammed passengers) for a ratio of 2 to 1.

Can we foresee lighter trains in the future where the weight ratio might reach 2 or smaller?

Thanks for any help!
 
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  • #2
If your passengers didn't mind sitting in the heat or cold, or in rainy or snowy weather, I don't see why you couldn't do what you have described. If they didn't want to have anything to eat or drink, or go to the bathroom, I'd say get rid of that bulky old train.

On second thought, why do we have a railroad often running alongside a perfectly good highway? I say, get those lazy passengers out of their train seats and make them run to their destination!
 
  • #3
SteamKing said:
If your passengers didn't mind sitting in the heat or cold, or in rainy or snowy weather, I don't see why you couldn't do what you have described. If they didn't want to have anything to eat or drink, or go to the bathroom, I'd say get rid of that bulky old train.

On second thought, why do we have a railroad often running alongside a perfectly good highway? I say, get those lazy passengers out of their train seats and make them run to their destination!

The first example was not practical, just curious how far weight could lowered while maintaining comfort and not raising the cost too far.
 
  • #4
There are several reasons why trains weight a lot more than just the passenger weight. Locomotives need to weigh quite a bit in order to pull a train, roughly 10% of the maximum weight train they will pull. Rail cars are also built heavy to provide the structural strength and stiffness to stand up to the service and to provide a safe structure in the event of a collision. As in many areas, much of these requirements are codified and there are no easy ways to avoid the resulting weight penalty.
 
  • #5
Weight is not a big issue on trains. It's not like they need to fly or anything, steel on steel wheels provide VERY low rolling resistance and, I'm sure as speeds get higher the air drag consumes the most energy.

I suppose starting and stopping the things wastes more energy the heavier they are, but it would probably be cheaper and more effective to simply recover the energy with batteries or back into the grid.

My point is, there are some vehicles (trains, ships) where high weight comes with a relatively low penalty. Might as well take advantage of this and indulge.
 
  • #6
This train was optimized for light weight:
http://en.wikipedia.org/wiki/SNCF_TGV_Duplex
but it still weighs 380t for 512 seats, or 742kg per seat, or 9 times the passenger weight.

Not brilliant, is it?

Weight is an issue for trains as well, because this limits their ability to travel in mountainous countries like Spain or South Korea or Italy - or worse, Austria, Switzerland...

As for the locomotive's weight, spreading the propulsion among all cars is a solution, used for instance on ICE 3:
http://en.wikipedia.org/wiki/ICE_3
but still about 1t per seat.

One of the reasons why cars are heavy is their need to sustain a contact with a wagon - something other professions would describe as a heavy collision, like a 76t wagon at 10km/h.
 

1. How does the weight of a train affect passenger weight?

The weight of a train does not have a direct effect on the weight of passengers. However, a heavier train may require more energy to move, which can lead to higher fuel costs and potentially affect ticket prices for passengers.

2. How does reducing train weight impact rail transportation?

Reducing train weight can have several positive impacts on rail transportation. It can improve fuel efficiency, reduce maintenance costs, and potentially increase train speed and capacity. It can also have a positive effect on the environment by reducing emissions.

3. What methods can be used to reduce train weight?

There are several methods that can be used to reduce train weight, including using lighter materials for train cars and components, optimizing the design of the train, and implementing more efficient braking systems. Additionally, reducing the weight of cargo being transported can also contribute to overall train weight reduction.

4. How can reducing train weight benefit passengers?

Reducing train weight can potentially benefit passengers in several ways. It can lead to lower ticket prices, faster and more efficient train service, and a more comfortable ride. It can also have a positive impact on the environment, making train travel a more sustainable option for passengers.

5. Are there any potential drawbacks to reducing train weight?

While reducing train weight can have many benefits, there are also some potential drawbacks to consider. It can be costly to implement weight reduction strategies, which may impact ticket prices for passengers. Additionally, it is important to carefully consider safety implications and ensure that reducing train weight does not compromise the structural integrity or stability of the train.

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