| Re: Line category according to EN 15528 [message #1252 is a reply to message #1251] |
Mon, 31 August 2015 11:18   |
Christian Rahmig
Messages: 151
Registered: January 2011
|
Senior Member |
|
|
Dear Dirk,
thank you very much for your feedback. I'll comment on it below:
Am 24.07.2015 um 18:02 schrieb Dirk Bräuer:
> [...]
>
> During earlier discussions on this "approach" we came to the conclusion
> better to handle "physical" values behind these rather "political"
> classes in railML. This means: Rather use "maxAxleLoad" and
> "maxMeterLoad" or "maxSpecificLoad".
>
> The reasons were:
> There are more local (country-specific) line classes than in EN15528
> which means that the enumeration from EN will not fulfil many practical
> demands. How should we classify a German line of CE or CM2..4 when only
> the EN15528 are allowed? And from the other way 'round: If we allow
> country-specific classes as CE, how should one compare or convert it
> with the other values? This would only be possible by "understanding"
> the physical background (axleload, meterload a.s.o.), therefore we
> should always name this background.
>
> There are also many examples where the classes do not fit the actual
> physical values (you could say, from a technical point of view, the line
> is wrongly classified - but the classification is political... For
> instance, the German line 6686/6709 is classified D4 but has apparently
> a load spread of less then 6 tons per meter.). So you cannot decide
> whether a certain vehicle or train can use the line if you only know the
> classification but not the actual physical values.
>
> ---
> I personally think that this earlier conclusion is still reasonable and
> therefore would still prefer the physical values such as "maxAxleLoad"
> and "maxMeterLoad" or "maxSpecificLoad".
>
> Best regards,
> Dirk.
>
> [...]
I agree with the conclusion reached after previous discussions: it makes
more sense to explicitly define the physical values of a line or track
and to derive a track or line category from it. It is also clear, that
there are national categories that differ from the international ones
and that you may have different categories for the same railway segment.
Further, I also agree with you that some category decisions are only
politically motivated and differ from reality. However, since political
decisions can be very relevant for railway operation, we should not
forget about such aspects - and if required include them in our schema.
So, for railML modeling I suggest the following:
If you are interested in the physical parameters of your line / track,
please use the more detailed and more specific parameters. As you
correctly mentioned, in most cases the line category can be "derived"
from these values. But if you only have the information about the line
category, deriving the physical values from it may cause errors i.e. for
political motivated category decisions. In this case, I suggest to use
the line category parameter.
Summary: Keep both options. Use the more detailed modeling where available.
Any further comments are still welcome.
Best regards
Christian
--
Christian Rahmig
railML.infrastructure coordinator
|
|
|
|
Members
Search
Help
Login
Home
