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The rain is pouring down over Avtjerna in Bærum after a long cloudy period. Viewed from the height of the addition to the new Sollihøgda tunnel, individual workers can be seen as pinheads on the ground. Large excavators come into play, shaping the terrain. Right now, they are working on an access road over Rustandbekken and down by Skoglund a bridge foundation is growing.
Statens Vegvesen is responsible for the Bjørum-Skaret section, which is the last stage of the major expansion of the Norwegian E16 road between Sandvika and Hønefoss. From day one they have used a model-based approach and continued throughout the planning, design and construction stages. Trimble's BIM solutions have opened up new and more flexible ways of organizing the work.
“Much of what we have done here is ground-breaking,” says Baard Sigmund Eikaas, BIM manager to the contractor Marthinsen & Duvholt.
He believes that parallel planning has been taken one step further on the E16 Bjørum-Skaret project. Eikaas, together with Pål Holmefjord Lorentzen, project manager at Statens Vegvesen, Mahmoud Timraz, project manager at Skanska and Ole Jørgen Braaten, project manager at the consultant Aas-Jakobsen, play key roles in the project’s digital collaboration. From their respective vantage points, they each tell how the planning and implementation has been optimized. All four benefit from model-based work to a greater degree than ever before.
Intuitive and efficient functionality makes it possible to view the models in plan, section, profile and in 3D. When the various tools are used together, this provides several advantages, especially when all central stakeholders are involved early in the process, such as this case study.
Developing the model in continuous interaction
The developer, Statens Vegvesen, has been a driving force in the introduction of a model-based working method and the use of BIM models. Even before the project started, it was clear that BIM would be used in the expansion of the E16. Skanska is the general contractor for the project, which has a contract value of SEK 3 billion.
Over the course of a couple of weeks, the consultant, contractor and builder created a rough model together, where all critical points were reviewed and linked to the schedule. After that, quantities and attack points for rock shafts were continuously added. As the model developed, it became more detailed and useful to more and more people on the project.
The model is developed through continuous interaction between the various stakeholders and is used by increasing numbers of professional groups out on the construction site. When the project is completed in 2025, large parts of the "as-built" documentation will also be model-based. One of the key goals ahead of the project was that as many disciplines as possible would be involved and benefit from the coordination tools. The background for this is the experience gained from the construction of the RV3 and 25 between Løten and Elverum.
“One of the most important things we learned is that there is so much to gain when everyone works in the coordination model. What is ready to build, and any changes, must be made visible to all departments and functions,” says Braaten. “When the designer and contractor see the same things in the same model, the risks of a misunderstanding are reduced. Changes and adaptations are communicated immediately because there is only one version that is updated continuously.”
Better cost controls and higher quality
It is often during the planning phase that the change of digital model is greatest. But at the E16 Bjørum-Skaret, the contractor has entered the picture earlier than usual. This made the entire design phase more dynamic.
The model also makes it easier to carry out online meetings. “The fact that we all have a common understanding provides greater flexibility,” says Braaten.
There are a steadily increasing number of specialist areas that connect to the model during the construction period. This opens up new possibilities during construction. Several processes that were previously managed via phone, email and drawings can now be handled directly within the digital model.
“Much of what we can do today was completely impossible just a few years ago,” Timraz points out. “You find problems earlier and can identify creative solutions during construction to a much greater extent than before. In addition, the model is of key importance in logistics planning,” continues Eikaas. This applies especially to road and VA planning.
An important improvement achieved on this project is the incorporation of the production planning into the modeling of structures, so that everything from the division into pour stages to the ordering of reinforcement for a given pour can be easily extracted from the model. This can only be achieved when the contractor and consultant work together closely and interdisciplinary - an important step towards an industrialized production process.
The threshold for changes and adaptations is lowered
From the air, you can see how the entire area is taking shape. Drone flights are regularly carried out and entered into the model to show progress. “From our standpoint, it provides a good and reassuring overview,” says Lorentzen.
Trimble SiteVision is used for visualization in the field, which works by entering BIM models using the combination of a mobile phone and handheld GPS receiver. The BIM model can then be viewed with high accuracy in real life with the help of the mobile phone's camera, the GPS receiver's position and modern AR technology. In this way, it becomes very easy to see how different solutions will look in reality.
Establishing a common understanding of the different challenges is particularly useful in projects with long planning times. A bridge often takes six months from design to construction. If you encounter challenges in the meantime, it usually affects several specialist areas and different phases of the work. “The value of making this visible early is enormous,” says Timraz.
Braaten emphasizes that various Trimble tools in combination with parameter controls have made the threshold for making changes lower than ever. “For example, we did a remodelling of a bridge in one day. The entire bridge deck with all reinforcements. This is something that we would probably spend 200 hours on if we worked in the old way. When it is quick and easy to make adjustments, we can also implement them if we see that a minor change would save time or increase quality.”
Accurate calculations
A challenge with BIM is that effort is required for everyone to feel secure with the model-based way of working. Some specialist areas are also more tied to their own traditional tools than others. “For individuals, it can take time to get used to standing out in the field with an iPad instead of drawings. But this is a natural development that our skilled professionals see the value in,” says Eikaas.
The experience of how everything is connected becomes clearer in a common coordination model and the interdisciplinary aspect is highlighted. “By gaining access to information-rich models, it also becomes important that we have the ability to really make use of all the information. In this respect we have come much further in this project than we had before,” says Braaten.
When it comes to quantities, Trimble solutions can make a difference in several ways. Among other things, reliable quantity calculations prevent both budget blow-outs and conflicts. “The better basis and the better structure you have, the lower the risk of conflict. But first and foremost, it's all about logistics and how we use our resources. When we poured the first bridge in the project, we had a deviation of 1.6 m3 of concrete out of a total amount of 1670 m3.
Ultimately, BIM makes it easier to achieve goals within time and cost. The risk factors are reduced and we can build in a more sustainable way.”
Even through the BIM models are becoming ever more detailed, there are still things that can be improved. “We were missing angles being shown in the model when measuring between points. In cases like that it’s a big advantage that we can give feedback and work together with Trimble to further develop the tools,” points out Eikaas.
In the future, he and the others anticipate that it will be possible to invite more suppliers and subcontractors to work on the model. In this way, for example, material orders will be automated to a greater degree than today. “The goal is for everything to be model-based. When all the history is collected in the same place, including comments and decisions that had been made, it provides more order and clarity. A transparent process also contributes to creating trust between those involved.
Just over a year after construction started, the images show that the E16 Bjørum-Skaret is on track. With each passing month, the reality becomes ever more similar to the model.
Trimble tools
Trimble Connect, Quadri, Tekla and Novapoint are the central tools when it comes to creating a common picture and understanding of infrastructure projects.
- Trimble Connect - a collaboration platform that allows you to visualize files and BIM models, organize project data and share information with others.
- Trimble Quadri - provides a common basis for all planning and where all models are gathered in a common coordination model that is updated in real time.
- Trimble Novapoint - allows designers to use one software tool to design roads, railways, tunnels, landscape and VA.
- Trimble Tekla - used to model constructions with associated reinforcements.
E16 Bjørum-Skaret
The work started in the spring of 2021 and should be completed in 2025.
Two tunnels make up around 50% of the total of the 8.4 km four-lane motorway to be built.
Five bridges and two major traffic intersections are to be built.
The section is part of a continuous highway between Sandvika and Hønefoss.
The expansion removes a major bottleneck and improves an accident-prone stretch of road.
