Arup Uses Parametric Design and BIM to Keep Kings Cross R8 Project on Schedule

By Steve Insley

Kings Cross Station became the largest railway station in Britain when it opened in 1852, and today, it remains one of England’s most important historic buildings. The area surrounding the station has a deep history and, despite its decline following World War II, is once again a London hot spot. 

Over the last 15 years, the Kings Cross neighborhood has undergone an urban transformation. New residential apartments, offices and retail shops, built in and around the area’s historical buildings, have drawn Londoners to a part of the city they used to avoid. 

Global engineering firm Arup has been heavily involved in the transformation of the historic neighborhood, most recently designing the structural elements for Kings Cross R8, two 13-story buildings that combine affordable housing with rental space for small businesses. 

Kings Cross R8 is adjacent to three brick tunnels that serve as the conduit for every train entering and leaving King’s Cross Station. The tunnels were constructed in the 1700s and are sensitive to movement, requiring each design milestone for anything constructed within a certain proximity to the station to get approval by London’s rail network operator. 

Taking time to complete the approval processes could have knocked the project off schedule, but Arup found a way to keep it moving using parametric modeling and BIM. 

Accelerating Design and Embodied Carbon Calculations 

Using the integration between Tekla Structures and Grasshopper, Arup could continue structural work at pace while design-milestone approvals were coordinated in parallel. 

“We had to produce a number of drawings for the network-rail approval process,” said Gordon Clannachan, senior structural engineer and project lead at Arup. “Although these needed to be done at an earlier stage than we would typically do on projects, they allowed the client to fast-track the approvals process prior to the main contractor starting on-site.” 

Parametric design, also called computational and algorithmic design, is guided by a set of interconnected variables, functions, and rules that generate or control the design output to a parametric BIM solution. Based on the parameters the engineer defines, the effects of any change to the design are automatically populated throughout the model. For example, Grasshopper takes the inputs, completes the calculations and produces an output that is applied to the Tekla Structures model. This gives engineers a tremendous productivity advantage by eliminating the time-consuming process of manually applying changes across the model. 

With parametric design at the heart of the project’s workflows, Arup could push and pull data and geometry to and from Tekla Structures, improving the efficiency of everyday tasks. “Using Tekla to automate the model was essential for this work. As the design scheme evolved, we were able to respond very quickly,” he says. 

The value of parametric design is perhaps most keenly felt during the structural analysis. With a manual workflow, determining the most efficient design is ordinarily an incredibly time-consuming process that involves manually changing each variable, running an analysis, noting the results and then repeating it an indefinite number of times. Incorporating parametric design into the workflow transforms this process. In the case of R8, Arup engineers created a script that automated the calculation of loads bearing down on the concrete columns and walls. This helped optimize the design and reduce the amount of concrete in the building’s foundations. 

Arup also used the Tekla-Grasshopper integration to develop scripts for calculating the embodied carbon footprint of structural elements. Arup built the carbon factors into the Grasshopper script and parametrically linked the data. They then used Tekla Structures to create templates to export the embodied carbon of every element by material and various embodied-carbon stages. 

“We have a responsibility to take ownership of the embodied carbon in the structures we design and to use our influence to reduce the carbon impact of our projects,” said Clannachan. “If you really want to influence carbon-related decisions, then you need to automate these calculations.” 

The calculations were reported against targets set for 2030 and beyond. 

Bringing Technology, People, and Data Together 

Connecting the right people to the right data at the right time was essential for keeping the project on schedule. The architecture team, coordinated their work using Trimble Connect, a cloud-based common data environment (CDE) and collaboration platform. The 3D models were uploaded to the platform shared across stakeholders for coordination, clash detection and recording comments, tracking related work and closing out completed tasks. 

“Email exchange isn’t the best way to track model comments, so we kept everything in Trimble Connect,” said Clannachan. “It’s really good to collaborate in a 3D environment so that nothing slips through the net. Trimble Connect also produces fantastic, colorized images for embodied carbon reporting.” 

Making Parametric Design Accessible 

Although parametric modeling may seem complex, direct links between BIM software and visual programming tools, such as Grasshopper, make it possible for structural engineers like Arup to leverage parametric workflows without prior programming knowledge. 

“I always try to look for ways to do each project better than the one before, rather than just defaulting to repeating the same methods,” said Clannachan. “Pushing automation into our workflows makes us more efficient in how we deliver projects and respond to changes. The structural team believed in what we were doing and put a lot of hard work into developing these tools, which we can now use on the next project.” 

With dynamic automation, increased accuracy and rapid iterations, the benefits of parametric design are undeniable. While it can be used for any project large or small, it’s especially advantageous in complex structures with unconventional architecture. Using parametric design takes the modeling process to the next level and makes it possible to streamline work, create high-quality designs, and deliver successful projects.