Creating a digital model and asset database that allows detailed interrogation of every component of the Docklands Light Railway has already delivered significant dividends, reports Tony Streeter.
Imagine a world in which costs fall, productivity rises, projects are delivered more swiftly, co-ordination is improved – and you have much better information about the state of your assets throughout their entire lifecycle. Those in the know will evangelise how technology is unlocking the benefits of Building Information Modelling, commonly known as BIM, which unites previously disparate information on projects and assets in an unprecedented way.
BIM processes deliver benefits at every stage of the life of any structure allowing a much greater level of collaboration and clarity of representation between project promoters, design teams, construction contractors, operators, maintainers, the supply chain and the all-important accountants.
The opportunities for every discipline seem virtually boundless and indeed the UK’s new HS2 high-speed railway is being built, operated and maintained in its entirety in a highly-detailed virtual world. This allows each element to be refined, optimised and analysed as to its impacts on every other component and its wider environment over a period of many years before a shovel even enters the ground.
In what is believed to be a world first on its scale, the Docklands Light Railway in the UK capital has already brought together state of the art digital survey and modelling technologies and created a unified digital system for its infrastructure that ties together drawings and models with relational databases that contain a wealth of knowledge about every component. Using both established internal experience from parent organisation Transport for London and new team members to bring fresh thinking, this means that the various lines that together make up eastern London’s light metro are now part of a fully digitally modelled railway.
No more information silos
DLR BIM Manager Andy Millar told TAUT that while BIM itself is nothing new, the decision to undertake such a large project – it has taken three years so far and is ongoing – was driven largely by the UK Government’s White Paper for BIM Level 2 adoption by 2016. The return on investment has been almost immediate through more obvious benefits such as avoiding repetition of surveys and investigative works. But there is so much more.
In practical terms, DLR’s adoption of BIM means that rather than having to search through drawings, or to physically inspect something themselves, anybody with access to the system’s Common Data Environment (CDE) can check the status of any individual asset – down to a platform seat, light fitting or even a poster frame. Using a customised version of a base package that can be bought ‘off the shelf’, the CDE has therefore amalgamated silos of information under a uniform framework that now gives a complete overview of both the physical and intrinsic properties of every element of the DLR. The data held in what the DLR terms its Graphical Information System (GIS) includes high-resolution aerial photographs, as well as 3D modelling of existing structures. Millar explained that due to the vast amount of legacy information generated in the 28 years of operation and management of the network, the view was taken that this was so disparate in nature that a new digital catalogue of the entire asset discipline portfolios – which cover 88km (55 miles) of track, 44 stations, two depots and two control centres – was deemed the most efficient way of populating the system.
Laser scanning of station areas and track formations has taken place, with the information gained being overlaid on survey data to create 3D component libraries – this is then updated element by element to build a continually evolving programme that allows users to click on any point and see all that is known about the asset in question. The aerial photography of the network is a core element of the GIS; this is linked to the DLR’s asset management database and other documents to bring all asset information together into one place – termed by the DLR as its ‘single source of truth’. Being cloud-based, the information in the GIS can be accessed – and this includes remote access by authorised third parties – via a dedicated web portal. Information is available as downloadable read-only documents to facilitate costing work to be undertaken, or initial designs to be developed; if it is then issued for the purposes of review, it becomes ‘quarantined’ to prevent further changes being made. A further facility under development will allow members of staff to update the system in real-time from a mobile device to report incidences of vandalism or damage using the GIS interface. Although this functionality is already commonplace on urban rail networks, it will add another valuable use to the BIM model in the creation and operation of a completely virtual network that perfectly mirrors the everyday physical one.
Millar also described how the scalable nature of the model allows for almost limitless further levels of detail to be added in the future as technology develops; one such example is the facility to provide
virtual walk-throughs utilising augmented reality systems.
BIM brings benefits
London’s DLR serves a major part of the eastern side of the UK capital, carrying hundreds of thousands of people every day and providing key connections through one of the world’s most important financial centres. As such, it forms a vital part of the country’s public transport infrastructure.
In 2014-15 the DLR transported more people than ever before in its history, and also achieved both its best ever customer satisfaction figures, and increasing departure and availability scores. Those in charge of
the system argue that BIM played its part in achieving that, although Millar adds that encouraging acceptance has formed a key part of the successful adoption of the new technology. While initial objections came from all demographics and age groups, Millar is pleased to note that through an educative and collaborative approach many of those who expressed reservations at an early stage are now among the biggest advocates having seen the benefits and efficiencies that the model brings.
These benefits have included significant cost savings – with a claimed minimum of GBP420 000 (EUR548 000) over the first six months of implementation – as well as successfully reducing both worker risk and passenger disruption. The need to access the network’s trackside (both during operational and non-operational times of day) has fallen with the reduced need for physical surveys, brought about by the ability to gather data in real-time from the BIM system.
Using BIM has brought a reduction in the risk through working on the DLR’s lineside in a number of key ways. These include:
1) Inaccessible live assets can be ‘virtually measured’ and data interrogated during operational hours, obviating the need for physical surveys.
2) Previously untraceable information is now readily available, further reducing the need for manned surveys.
3) The ability to remotely determine which assets will become life-expired at any given time helps preventative maintenance (reducing potential disruption) and further reduces the need for surveys.
4) Collaboration of all parties at the design stage – made possible by the Common Data Environment – helps in the elimination of risk during the design process.
Do it once, do it right
The other key benefit of BIM is the value for money it brings at all stages of planning and delivering new projects – everything from new lines to upgrades on both major and minor systems. Internal and authorised external parties can access the same up to date pre-construction information, helping to make the processes of tendering and cost definition both more accurate and efficient.
At the design stage, remote access to such information for suppliers and contractors who may be geographically distant brings further reductions in time and cost: as a specific example, providing a model of Beckton Depot to Thales to underpin the design of signalling upgrades saved the DLR GBP300 000 (approx. EUR392 000) in quoted survey costs. The DLR has separately saved a further GBP120 000 (approx. EUR157 000) in quoted survey costs by being able to confirm platform accuracies using trackside laser survey information.
Further cost savings – as well as increasing the safety of workers – can be achieved in the construction phase through the easy access to surveys, 2D/3D CAD infrastructure information and aerial photographs from anywhere and at any time.
The success of the DLR in using BIM means the Docklands-developed system can be used to showcase best practice as other areas of Transport for London (TfL) look to develop their own BIM systems. In the London Rail directorate this includes TfL’s Overground heavy rail suburban system and London Tramlink (but not the world-famous Tube, which is separate). Also joining the TfL family in due course is the massive 136km (85-mile) Crossrail project, which is due to open in stages by 2019.
The new BIM system is also in the process of being accredited by Lloyds Register. If successful, DLR will be the first public body to achieve such accreditation from the Lloyds Register, which is then expected to use the DLR method to create compliance criteria for similar organisations.
Thanks to Sara Kent and Andy Millar from DLR. Image courtesy of Transport for London.