Barge canal weight limit.

[Vladki]

After long playing standard I decided to give a try to experimental. And quickly hit into problem with barge canals. It has a weight limit 80 tons and most barges can load 50t. But then they cannot be used in a set with unpowered barge "trailer". The total load is over the limit. Is that intentional?

[jamespetts]

The weight limit is per vehicle, except on bridges where it is per convoy (but the limits are higher), so this should not be a problem. Can you be more specific about the nature of the problem that you are having?

[DrSuperGood]

I thought the weight limit was "axel load". On everything except bridges pathability is binary (either allowed or not) and independent of load (full or empty). Bridges do take the actual weight into account so it is possible for a full convoy to be unable to cross a bridge it could when empty.

[Vladki]

The barges could go empty, but when they wer loaded I got no route message.
I'll try with freshly compiled (linux) version and tell you.

BTW: what is the axle load for a boat? Division by zero?

[DrSuperGood]

BTW: what is the axle load for a boat? Division by zero?

One could argue why canals even have a weight limit in the first place... The weight of a ship is pretty much irrelevant to canals I would imagine since by definition of it being a ship it is displacing its weight in water so the underlying structure has approximately the same force applied to it at all times. If a canal is not moving a 60 ton barge it will have 60 tons more water in that section which would otherwise be displaced by the barge. Since canals are waterways (provide a path for water to flow) the displaced water generally becomes irrelevant as it would quickly flow away.

If anything the current canal system should be changed to use some metric of ship size rather than weight. All the way types for different barge types etc can then be removed and instead replaced generically with "water". The ship width would then form a way type restriction with very narrow canals being unusable for bigger (wider) ships. This would even be more realistic I would imagine since canals quote suitability with some size metric (eg Panama Canal allows Panamax ships through). In real life it is multi-dimensional however it could be simplified to cross-sectional or even just how wide.

[Vladki]

Tested with version sim-ex 11.35, Pak128.Britain-Ex-0.9.1 still problem. How to reproduce:
Build a barge canal connecting e.g. coal mine and power plant. Build two tiles long stops. Buy diesel barge with steel hull unpowered barge for bulk goods. Send this convoy to carry coal between the mine and power plant. It will get to the mine, load fully, and then tell you "no route". It won't even get to the depot.

[jamespetts]

I can't reproduce this with the latest development version: I think that this must be one of the bugs that have already been fixed, and are awaiting the release of the development version when further work has been done on it.