What CAD software is used for infrastructure design?

[Crithylum]

I’m wondering what computer aided design software is used by the railway to design infrastructure. Is there a single piece of software which contains everything, or is different software used for different parts of infrastructure design and maintenance?

 

[civ-eng-jim]

Rail systems use Bentley MicroStation with various add-ons or variants for discipline specific tasks. .dgn format

Pway use:
Bentley Rail Track/Power Rail Track
Bentley Open Rail
ClearRoute (gauging)
Trimble for setting out files.

 

[Belperpete]

Back in BR days, S&T used to use its own specialist CAD software for things like signalling plans and circuit design. I understand it was based on commercial software (autocad?). After privatisation, Railtrack and then Network Rail, plus the various private supply companies, continued to use that software, under licence from one of the suppliers who supported it. However, I am not sure what the current situation is.

Network Rail did have a project that was intended to produce various different types of CAD design from an underlying database, but I understand that they have given up on it.

 

[Kentish RYS]

Back in BR days, S&T used to use its own specialist CAD software for things like signalling plans and circuit design. I understand it was based on commercial software (autocad?). After privatisation, Railtrack and then Network Rail, plus the various private supply companies, continued to use that software, under licence from one of the suppliers who supported it. However, I am not sure what the current situation is.

In terms of signalling it is Bentley, what is now MicroStation. I think rather than specialist software, it was mostly symbol sets and the like, though there were add-ons such (I know of one for Signalling Plans by Westinghouse and one that was Alstom, no idea of lineage of both). The Bentley choice was made apparently as the USA DoD and DoT and maybe some other UK places were using it (maybe our MoD for commonality with the USA? It was a long time ago I had the conversation with some people who worked in the BR(S) Signalling Design Office at the time) so that the product would continue to be supported. However, what went on to be AutoCAD became much cheaper to licence and more commonly taught in colleges and such. Bentleys product on the other hand becoming a product used by specific professions only with licence for a year costing over a thousand pounds in the 2010s. There are tools to convert to AutoCAD file format from .dgn, however these are not good enough for critical drawings as details get lost or altered in the process so the drawings are set in the Bentley format without (at least partially) by person recreation and then independent check cycle.

 

[Belperpete]

As you say, the tools for converting between the two formats were nowhere near good enough for drawings of safety critical designs. In my experience, sometimes the conversions were barely readable.

I suspect that this was partly because of the specialist symbol sets used on signalling drawings. The Plans and Circuits software also have a level of intelligence that relies heavily on things being drawn on the correct levels. It may also have been because signal engineering designs are very rarely standard 2D or 3D designs.

The Plans software, for example, can cope with objects that have linear coordinates on a drawing that has multiple changes of scale, and perhaps no scale at all! British signalling plans are only scaled linearly, in one dimension, whereas most CAD drawings are scaled in two or three dimensions.

The circuits software was primarily intended for designing relay interlocking circuits. It could automatically allocate contacts, and produce analyses, for example.

 

[JKF]

I think highways designers mostly use microstation too, or at least used to a while back when I was a CAD person. It seemed quite a non-standard option at the time with AutoCAD products the default for general construction. I wonder what the specific advantages were that saw microstation used for transport projects?

 

[sturmey_archer]

Autodesk have made a good go at the infrastructure market with their Civil3D software, and various add-ons for highway alignments and drainage analysis, but it does seem like MicroStation is the infrastructure sector's tool of choice.

Using X and Y (or Easting and Northing co-ordinates like on an OS map) works ok for general construction, but even for things a few kilometres long you quickly start to get distortion when you build things on a spherical planet. As I understand it, MicroStation works better the custom co-ordinate systems (eg: Snakegrid) that you use to make 2D drawings work with a long wiggly route on a 3D planet.

Big projects also use a Common Data Environment - a big shared file store that also tracks things like document versions, and keeps a record of who has checked and approved changes... the software keeps an audit history and acts as an ISO9001 Quality Management System. For whatever reason Bentley's ProjectWise seems to be the industry's favourite tool for this job, and whilst you can use this to store AutoCAD files, it integrates more smoothly with Bentley's own MicroStation software.