The success of any infrastructure project depends significantly on its constructability; this involves designing projects with their practical execution in mind. Delays, costly redesigns, and unforeseen obstacles are all possible consequences when projects are not designed with constructability at their core.
Modern advances in CAD (Computer-Aided Design) and BIM (Building Information Modelling) provide powerful tools that, when used effectively, can ensure that constructability is a fundamental aspect of project design from the very beginning.
In this article, we explain how the Whitfield Consulting Services (WCS) team use these as facilitation tools for constructability, eliminating potential issues before they arise and maximising collaboration at every stage.
Why constructability matters
“By constructability, we mean examining how the permanent structure is going to be built, considering the stage-by-stage process of construction. This involves looking at how each part of the structure transitions through various phases until it reaches its final state,” says Jeremy Barnes, Technical Director at WCS.
“Focusing on constructability from day one allows us to deliver solutions that work in the real world,” adds Dave Crumley, CAD/BIM Manager at WCS. “We embed constructability into the heart of our designs. By integrating CAD and BIM from the start, we ensure a smooth shift from design to construction, reducing risks and improving teamwork.”
An advanced approach to CAD/BIM
Historically, small and medium-sized design firms often limited their CAD work to basic drawings that showed the design’s intent without fully including other design teams or models. This approach does not provide the level of detail and foresight that today’s complex projects require.
“Our CAD/BIM department operates with the belief that design must go beyond the basics to meet the rigorous demands of Tier 1 clients,” says Dave.
Using state-of-the-art tools, the WCS team creates models that integrate design, construction, and operational requirements, allowing them to visualise, plan, and coordinate projects in unprecedented detail.
“Our team works alongside engineers to ensure every possibility is considered and unworkable ones are ruled out,” explains Dave. “This allows us to deliver constructable designs that avoid unnecessary surprises.”
Tools to ensure constructability
The WCS approach to CAD/BIM focuses on using advanced tools to address the key challenges of modern construction projects. These tools support:
- Eliminating risks: Accurate, data-rich models help identify and resolve potential issues before construction begins.
- Facilitating collaboration: Shared models within a Common Data Environment (CDE) allow all stakeholders to work from the same plan, improving communication and reducing errors. Here all the data from, for example, surveys of buried cables or third-party structures, is included and accessible for all involved in the project so potential issues can be identified early. This means that the design of foundations for a substation, for example, is not being created in isolation from factors that could impact the construction of that substation.
- Streamlining construction planning: Integrated models help plan construction sequences effectively, allowing for a stage-by-stage breakdown of activities. This ensures that materials, equipment, and labour are utilised optimally, reducing waste and delays while improving overall efficiency.
- Meeting rigorous standards: The team’s knowledge enables them to produce designs that meet the stringent requirements of clients such as Network Rail, National Grid, and HS2, tailoring each project to exacting standards for compliance and efficiency.
Constructability in action: case studies
Midland Main Line Electrification
Network Rail is upgrading and electrifying the Midland Main Line – a major railway line from London to Sheffield in Yorkshire via the East Midlands – to allow electric trains to run the full length of the service; a vital project to progress the decarbonisation of the UK’s transport system.
SPL Powerlines was tasked with installing 447 single track kilometres of overhead line along the rail corridor, with the scheme divided into eight route sections.
We collaborated with the SPL Powerlines’ team on phases RS1 to RS6 of the programme, lending our expertise in areas such as geospatial modelling.
“Our team has been instrumental in helping SPL Powerlines model CAD drawings geographically within SPL’s Snake Grid geolocation system,” says Dave.
“This collaboration ensures that all design elements were accurately mapped and aligned with the geographical realities of the project site, further enhancing the precision and reliability of the BIM process.”
With multidisciplinary teams working across the eight route sections, SPL Powerlines needed to ensure that everyone had access to the latest design information. To help meet this challenge, WCS collaborated with SPL on its use of advanced technologies and processes, including point cloud technology, federated models, Itwin integration, and robust CAD Quality Assurance processes. “Together, we set a new benchmark for efficiency and accuracy in infrastructure projects,” says Dave.
SPL Powerlines won a Bentley Systems 2024 Going Digital Award for its outstanding use of technology in the Midland Main Line Electrification project.
“Our expertise in geospatial modelling and CAD integration played a significant role in the success of the project,” adds Dave.
Downs Park Road Overbridge
One of our most complex projects to date has been the Downs Park Road Overbridge in Hackney, East London. This 154-year-old road bridge, spanning two electrified railway tracks, required urgent restoration. The challenge was to replace the deteriorating deck while accommodating multiple utility services, including telecoms, power, and drainage.
To meet these challenges, the team designed a fanned filler beam steel deck and worked closely with our client using a point cloud survey of the existing bridge. This highly detailed 3D survey allowed us to create an accurate surface model and identify any potential issues long before construction began.
When it came time to erect the new bridge, everything fit perfectly – exactly as planned. The project was a success, and it is an excellent example of how the team’s approach to CAD/BIM delivers results in even the most challenging circumstances.
“The project truly showcases our ability to devise engineering solutions to complex problems that deliver on practicality, sustainability, durability, cost, functionality, and ease of maintenance,” says Mohamed Omar, WCS’s Civil Design Engineer on the project.
The client, Murphy, was pleased with the outcome: “Thank you Whitfield Consulting Services for such a seamless design and for the technical support,” says Kieran Moore, Engineering Manager – CRE at Murphy.
Control Period 6 (CP6) bridge strengthening projects
Working with Murphy on three CP6 bridge strengthening projects, WCS led the design at GRIP 3, GRIP 4, and GRIP 5 stages. During design reviews, the team provided 3D models that could be rotated and viewed from every angle. This allowed the construction team to thoroughly examine how materials would be installed, explore alternatives, and determine whether a MEWP (Mobile Elevating Work Platform) or scaffolding would be more suitable for the job.
In these scenarios, when you have a small window of opportunity – perhaps only two weekends of railway possession on some Network Rail projects – every second counts. Delays can lead to losses of hundreds of thousands of pounds. By ensuring every element was meticulously planned and visualised beforehand, the team helped avoid costly disruptions and ensure smooth project execution.
Expertise across disciplines
The WCS CAD/BIM team is composed of experts from diverse backgrounds: engineering, visualisation, animation, and compliance. This multidisciplinary approach allows us to tackle challenges from multiple perspectives, ensuring constructable and practical designs.
Dave manages the department, supported by a diverse and experienced team across two offices.
“The CAD/BIM technicians are constantly pushing the boundaries,” says Dave. “We’re always investigating new digital tools to improve project visualisation, integrations of bills of quantities and other metadata and facilitation of project scheduling.”
WCS’s advanced approach to CAD/BIM ensures that constructability is embedded in every project, delivering designs that are efficient, practical, and compliant with industry standards.
If you have a rail civils or electrification project, or a power and energy project, or are looking for preliminary drawings to support a tender submission, we would be happy to show you how we use our skills. Please contact us.
