The development of London’s new high-frequency underground railway line embodies the many benefits that BIM can bring to the process of design, engineering and construction.
The 118-kilometre line is currently the largest railway and infrastructure project in Europe and will entail the construction of 42 kilometres of new tunnels in the greater London area.
Work on the ambitious scheme began in 2009 following several decades of proposals and preparations. Upon its scheduled completion date of 2018, Crossrail will knit together the UK capital with its surrounding regions and suburbs via the provision of high-frequency passenger services connecting parts of Berkshire and Buckinghamshire to Essex and South East London via the centre of the city.
Building Information Modelling (BIM) is playing a pivotal role in the development of Crossrail, particularly given the sheer scope and complexity of the project and the bewildering range of sub-projects and contracts it encompasses.
Crossrail's developers are using a centralised set of linked BIM databases to incorporate around a million CAD files into a single information model, in order to radically enhance accuracy, consistency and project coordination.
This BIM database accounts for just about every element involved in Crossrail's development, encompassing 25 design contracts, 30 main works contracts and 60 logistics main works contracts.
All of the designs included follow a consistent set of 3D processes and rules, permitting the creation of detailed static as well as animated models of various aspects of the project in their full complexity literally years before they reach fruition.
The ability to visualize the project in its entirety via a single 3D model, as well as access other intangible data incorporated into the model via BIM, radically improves coordination between the disparate parties to its development. This in turn avoids potential clashes between the various elements of the project, such as the duct work performed by mechanical engineers and the concrete or steelwork which is under the remit of structural experts.
The use of BIM also maintains the accuracy and consistency of all shared information, with any updates of individual CAD files re-integrated into the centralized set of linked databases.
Crossrail's developers hope it will be the first major infrastructure project to fully embody the benefits of BIM, achieving long-term cost savings via greater accuracy of information as well as improved coordination between various stakeholders.
"Crossrail is pioneering the use of Building Information Modelling in Europe on a scale that has not been undertaken before," said Crossrail chief executive Andrew Wolstenholme. "This has directly enabled us to develop innovative engineering design solutions, minimise waste and reduce future costs for maintaining the railway."
Greg Bentley, CEO of Bentley Systems, which worked with Crossrail in the establishment of a specialized BIM Academy for the project, pointed to collaborative BIM as a "particularly advantageous innovation strategy" for the UK, which can improve lifecycle information quality in addition to yielding benefits during construction.