The logistics behind its planning, design and construction have been immense. It is the successful employment of building information modelling (BIM) concepts that have helped it progress and remain on-time and on-budget.
BIM is a shared knowledge resource for information about an asset, which creates a reliable basis for decisions during its life-cycle, from design through construction to operations and maintenance.
BIM has been successfully employed on large infrastructure projects internationally and Crossrail is perhaps the most prevalent of the success stories out there. The use of BIM processes on the project became a major catalyst behind the United Kingdom’s adoption and mandate of BIM.
Malcolm Taylor, Head of Technical Information at Crossrail, visited Australia in March and spoke about the role of BIM on the project at Bentley Systems’ BIM Advancement Seminars, Incorporating Crossrail’s Information Academy.
During his visit, Mr. Taylor spoke to Roads & Civil Works Magazine about BIM’s role in Crossrail, its success and the major lessons learnt, and how those learnings may also apply to Australia’s own infrastructure sector.
Crossrail is the massive undertaking to deliver a new 118-kilometre railway line from Reading in the west to Shenfield and Abbey Wood in the east. The project passes through Heathrow and includes the construction of twin 21-kilometre tunnels under central London. Still under construction, the newly named Elizabeth Line is scheduled to be fully open in 2019.
The project incorporates23 different design contracts, 34 advanced work contracts and 45 large main works contracts. Mr. Taylor says that all of these contracts had an extraordinary number of interlinked information interfaces within the project from the beginning.
He says that there were a number of logistical challenges on the project as early as 2008, when detailed design work began.
“We were at a crossroads. It was a point of time where we saw some real challenges in how to work within a large project where we have so many different people to work with,” he says. “The question was ‘how do we get all of this to work in the same type of system?’”
He explains that the concept of BIM wasn’t fully developed at the beginning of Crossrail, but the idea of putting all the information in a common data environment just seemed to make sense.
“Back in 2008 we were looking at the fact that, from a 3D modelling perspective, we’ve got all of these different designs from different designers that have to fit together.”
He says designers would traditionally submit CAD drawings which would then be compiled into the final design. However, if designers are working to different standards and specifications, putting the final design together becomes more complicated and time consuming.
He likens it to a LEGO set. Different people with their own LEGO sets are coming to the table and trying to piece together the bigger picture, although with some blocks that might not match. The aim was to get everyone working with the same LEGO set and contributing to the overall picture with the same types of blocks.
“When things don’t fit that means money and time,” he says. “On a project when you have one designer you don’t need to worry about that too much. Once you start to add different people, disciplines and organisations, that’s really where BIM can really add value, and has come to the fore.”
“We had all of this information already and we just saw the light. The technology was available, the question was just about centralising it, putting together strategies and approaching the different groups and getting them to work together.”
The solution was to create a centralised set of linked databases on which people can work using the same design processes and naming conventions. The project team utilised Bentley Systems’ collaborative and content management software, ProjectWise and eB for this task. Around the same time, a new British Standard called BS1192 was introduced, it established a methodology for managing the production, distribution and quality of construction information, including that generated by CAD systems, using a disciplined process for collaboration and a specified naming policy. Working with Bentley, the parameters defined within BS1192 were configured within ProjectWise and eB, and provided a centralised database or ‘single source of truth’ for the project, together with automation of a standard workflow.
Today, ProjectWise is available out of the box with a BS1192 template in place as standard, and eB is available with much of the functionality used by Crossrail for information workflows. Within eB, workflows were used by Crossrail for their asset breakdown structure, all contract administration, project information requests, snagging and many other project management activities.
For Crossrail, BIM became the process of generating, building and managing the multiple works contracts with 5 million documents and 300,000 CAD model files through the life of the project by using model- based technologies within one Common Data Environment (CDE) of project information. This includes physical, environmental and commercial data on every element of the overall project.
“One of the prime concepts of BIM is creating a common environment people can work with. It’s just connecting the dots,” says Mr. Taylor. “The designs fit together in the 3D world before they even hit paper. For us it wasn’t a eureka moment, it took two years to put it together.
“Because the world is becoming data-centric, and information centric- you need far more software integration to help provide access to information that can be used by everyone.”
Any major decisions on the Crossrail designs could then be made by simply accessing the centralised database. “By joining up that wealth of information and data, decision-making becomes much more effective and stronger. We’re able to now use that information in a more efficient way,” adds Mr. Taylor.
By 2011, the potential of BIM was fully realised on the project. It then became a project-wide concept for Crossrail.
“I don’t know how we would have done it without it. It was the most efficient and effective way of managing over 100 different contracts,” states Mr. Taylor.
The benefits have been numerous cost and time savings, as well as reduced errors due to the single digital source in which the entire project’s designs are compiled.
“We’re running to schedule, running to budget and everything technology-wise is working. The interesting thing is that we’ve done everything to this system and it’s actually quite straightforward. All of that communication and information is in one place,” he says.
Even though London’s Crossrail is still in the midst of construction, Mr. Taylor asserts that BIM has proved to be an invaluable set of processes in design and construction, one that is a great example to follow around the globe. “If we can do it on Crossrail, you can do it on anything,” he says.
Photo credit: © Crossrail Ltd