Home » railML newsgroups » railML.infrastructure » [railML3] Modelling of bridges
[railML3] Modelling of bridges [message #3010] Thu, 09 June 2022 11:56 Go to next message
Thomas Langkamm is currently offline  Thomas Langkamm
Messages: 25
Registered: April 2019
Junior Member
Dear all,

I'm rather confused how rail bridges (2 tracks crossing each other via a bridge, like here: https://www.google.de/maps/@52.4875682,13.4580887,673m/data= !3m1!1e3) are modelled. (I apologize if I missed something obvious, but after browsing through the forum and wiki for half an hour I gave up and thought I'll ask here.)

overCrossing/underCrossing appear to be designed for something other than a rail that crosses/is crossed, however, it allows the type "railway" for is:crossesElement (https://wiki3.railml.org/wiki/IS:crossesElement#3.2). Since we don't have a "bridge" element anymore, it seems that we should use one of these two?

If this is incorrect, what is the correct modelling?

If this is correct, then this leads to some questions:


  1. Say tracks A crosses over B. Would we have 2 elements, one overCrossing for B and one underCrossing for A? If so, would either have 2 elements "networkLocation" to reference the netElements? In this case we can't seem to distinguish which one is at the top and which one is at the bottom.

  2. Or do we have just one element? If so, which one? IS:crossing appears to be out, as I read "A crossing is a place where two railway tracks intersect[...]" as that there is a physical connection between the tracks.

  3. How would the netElement structure be? If we choose to separate netElements at the crossing point, we would have netElements A1/A2 with a netRelation A1_A2 and B1/B2 with netRelation B1_B2. But would we have a netRelation between A1_B1, A1_B2, A2_B1 and A2_B2 (navigability=none)?
Best, Thomas

Re: [railML3] Modelling of bridges [message #3014 is a reply to message #3010] Mon, 13 June 2022 23:07 Go to previous message
christian.rahmig is currently offline  christian.rahmig
Messages: 447
Registered: January 2016
Senior Member
Dear Thomas,

in railML 3 a railway track crossing another railway track via a bridge can be modelled using the elements <overCrossing> and <underCrossing>. Assume that in the following example Track A passes over Track B (whereas A and B shall be the IDs of NetElements).

<overCrossing id="ocr1" constructionType="bridge">
<spotLocation netElementRef="B" ... />
<crossesElement type="railway" ref="A" ... />
</overCrossing>
...
<underCrossing id="ucr1" constructionType="bridge">
<spotLocation netElementRef="A" ... />
<crossesElement type="railway" ref="B" ... />
</underCrossing>

So, in summary: the bridge of a railway track over another railway track is modelled via two elements (one overCrossing and one underCrossing). What should be investigated in detail, is the question how both elements can be linked with each other. Let's put this topic on the agenda of a next Schematic Track Plan (SCTP) use case working group...

Best regards
Christian


Christian Rahmig – Infrastructure scheme coordinator
railML.org (Registry of Associations: VR 5750)
Altplauen 19h; 01187 Dresden; Germany www.railML.org
Previous Topic: [railML3]crossesElement/[railML2.5]crossedElement
Next Topic: [railML3] meaning and purpose of speedSection.isTemporary is unclear
Goto Forum:
  


Current Time: Mon Jul 22 15:43:52 CEST 2024