Digital Engineering techniques and processes are enhancing the delivery of major rail projects, improving quality, optimising programmes and helping to control costs…
It is well known in project management circles that there are three primary controls which affect project delivery, ‘scope’ (features and quality), ‘time’ and ‘cost’. These are also referred to as the ‘project management triangle’ where each side represents a constraint. One side of the triangle cannot be changed without affecting the others. These three constraints are often competing constraints: increased scope typically means increased time and increased cost, a tight time constraint could mean increased costs and reduced scope, and a tight budget could mean increased time and reduced scope.
Major rail projects are not immune to this and indeed, due to higher public expectations, ever tighter programmes and environmental challenges, together with relentless budget pressures, the need for improvements in the way in which projects are delivered has never been greater. The application of digital engineering tools and practices to the design and construction allows the constraints of the project management triangle to be stretched as never before, allowing projects to be delivered faster, better and cheaper.
Digital engineering on the Middle East metro
Building Information Modelling (BIM) has been around for about 20 years as a technology, but only in the past five years or so has it become mainstream, with clients as well as construction and design teams, recognising the opportunity to deliver better project outcomes using an efficient, collaborative process. Building a model, a digital prototype of a facility, significantly improves quality by reducing errors in design, allowing project delivery times to be much more predictable and therefore reducing risk. However, it is not just about building a model, there are a whole series of benefits which are only really apparent when you put BIM at the core to your design process, rather than just adding 3D modelling as a parallel activity, as is often the case.
On this metro project, the scope, aggressive schedule and ambition of the scheme meant that the only way to deliver the project was using global collaborative teams designing and coordinating in BIM. For example, Atkins’ role as lead designers drew in expertise from around the globe supporting teams in the UK, Middle East, India and Hong Kong. In the Hong Kong multidisciplinary design centre, from the outset it was decided to collocate the key members of the design team in a single office, so that the lines of communication were short, to encourage close collaboration. The other key strategic decision was to train architects and engineers to use BIM applications to develop and coordinate their design models, rather than having a separate team of BIM modellers working from 2D design drawings created in isolation from the BIM process.
All the project drawing deliverables were derived from the models, with the exception of the reinforced concrete detailing which was developed in 2D for speed, to meet the aggressive construction programme. Although there were notionally only 2 work stages, more than 100 early works packages were delivered for each station, to support this accelerated schedule.
Digital engineering techniques employed on the project included the use of automation in the process of scheduling for the stations, a customised solution was also developed for delivery of submissions, necessary due to the complexity of the project and frequency of submissions required to meet the programme. A digital issue tracker was also deployed to assist the design coordination process and to provide KPI’s and dashboards to communicate progress to management teams.
Track and tunnel alignment
The development of track and tunnel alignment is an intensive process requiring an in depth understanding of rolling stock dynamics, as well as accommodating the essential safety and traction systems to ensure the smooth running of the railway. While there are software solutions such as Bentley Rail Track which can assist designers, translating these designs into real world construction information is challenging, and error prone.
Bridging the gap between design and construction, Atkins have developed tools to help create detailed construction models and a fully dimensioned alignment design, detailing the track alignment, train swept path analysis, tunnel axis and track form surfaces, along with evacuation walkways and envelopes.
This information is output as a 3D model which can be used for coordination of track and rail systems, and exported to Autodesk Revit for detailed design or Autodesk Navisworks for coordination.
These solutions have been successfully used on projects such as the North Island Line of the MTR in Hong Kong, and Doha Metro.
Digital electrification design
Atkins’ transportation division is developing a number of software tools to assist the design of railway electrification overhead line equipment. The interlinked suite of programmes, known collectively as TADPOLE (Tools Aiding the Design and Production of Overhead Line Equipment), uses automation and common data sources to meet current technical and programme demands in the UK marketplace.
The two-year project, which is part of the government innovation strategy for digitising the railway, focused on railway electrification. The team has developed approaches that increase the efficiency and validity of data through all stages of the asset lifecycle.
Exploiting the modular functionality of TADPOLE, the layout plan tools and subsequent wire run validation spreadsheet and dropper generator have been used extensively on the Midland Main Line Electrification works, Great Western Electrification and North West Electrification projects in the UK.
The TADPOLE cross section tool has been deployed on the Great Western Electrification project demonstrating the benefits of automating cross section design. Design teams in the UK, Scandinavia and India to date have generated over a thousand cross sections and material allocation sheets. The tool ensured consistency in design solutions and quality whilst greatly reducing design timescales in a challenging project environment.
The future of design?
While it is clear that digital engineering is making significant improvements on project delivery today, advances in technology which are currently in development look set to have an even greater impact in the future, with the use of generative design. In essence, what this represents is the adaptation of machine learning into the process of design, drawing upon the wealth of existing data from all walks of science and engineering. Then developing a graph of the connections between objects and systems used in previous solutions, which allows software to execute thousands of iterations of a design, to converge on an optimum solution which would never be possible using traditional methods.
An example of this is what Autodesk have been doing with Airbus to optimise the design for a partition frame separating the galley and passenger compartment on the A320 aircraft. There were constraints in terms of thickness, strength, mounting points for jump seats and attachment points to the airframe. Using these constraints and applying an algorithm derived from the growth patterns of slime mould single celled organisms to generate 10,000 design options resulted in an intricate 3D printed component which was 45 per cent lighter than the standard component.
To meet the increasing challenges of rail project delivery, the use of optimised, innovative digital solutions will help release the project management triangle constraints, and allow us to achieve outcomes which are better, faster and cheaper.
And in the future, the pace of change will be faster and the solutions ever more innovative and tightly optimised. Are you ready for the challenge?
Brendan McFarlane – Atkins Global