Rail Engineering - WSAtkins Rail Or Balfour Beatty

Rail OLE Design The overhead line electrification tools were developed for the WS-Atkins / Balfour-Beatty Joint Venture (WSABBJV) to help design improvements to the West Coast Main Line (WCML) to allow the running of high speed trains. S u r v e y D a t a The first step in the design process is to create a 3D model from survey data. The survey data consists of discreet points (e.g. the base of a structure, the position of a bracket etc.) and points along linear features (e.g. wires, rails). Each point is coded. The code has two parts. The first part identifies the type of point; base of mast, rail etc. The second part qualifies the point, i.e. mast number or rail number. C o d i n g P r o b l e m s Throughout this part of the project coding was a major problem. It was quite difficult to get everyone to agree what items should be recorded let alone what they should be called and subsequently coded as. It would have been very useful to develop a project glossary at an early stage to give everyone a common basis to work from. Unfortunately everyone was under considerable pressure to get on with the job. This meant that survey teams were out on site collecting data before the coding structures were agreed, leading to duplication of effort, missing data and a considerable amount of head scratching. 2 D t o 3 D Because the engineers work from 2D drawings the 3D model had to be converted into a series of 2D drawings. A single plan view (layout) is accompanied by a vertical elevation at every structure (cross-section). These are generated automatically. I n t e l l i g e n t C e l l s

The biggest saving in draughting time was achieved by using 'intelligent cells'. These custom designed tools place components such are registration arms. The tools know what type of item they are placing. Various parameters such as maximum and minimum lengths are read from text files. 'Snap-points' are determined from markers in the cell libraries. The detailed geometry is built into each tool - this reduces the customisation available to the end users but simplifies the programming dramatically. The tool restricts the placement of each component so that each one is placed only in a proper configuration. An extensive testing and QA procedure ensured that every component placed by the tools met with all the safety and design criteria. S p r e a d s h e e t s a n d A n n o t a t i o n

The designers make extensive use of spreadsheets for performing various engineering calculations. A two way link was provided to the spreadsheets so the position of various items could be exported to a spreadsheet, a set of calculations performed and an updated set of coordinates were fed back into the drawing. The tools changed the position of items in the drawing to match the new updated coordinates. W e r e t h e y w o r t h i t ?

WS-Atkins estimate the tools saved them 10 million GBP.