NCC completes BIM-based rail project
NCC is expanding the Svealand railway line with double tracks on the stretch between Strängnäs and Härad in Sweden. Close collaboration with the design engineers and a strategic use of digital BIM models from the early stages has enabled a smooth and efficient project.
Illustration from Trafikverket.se.
The Swedish contractor NCC is about to complete 8.5 kilometres of dual-track railway, a three kilometres long rock tunnel, and nine bridges on behalf of Trafikverket, the Swedish Transport Administration. The engineering company ÅF in Jönköping has designed the project model in Trimble´s Novapoint and Quadri BIM tools as a building basis for the actual construction. The goal is to complete the construction in summer 2018.
Daniel Ring at NCC´s department of large projects has been the project manager for the project since it started in 2014:
“Turnkey contracts have become more and more common for NCC. The contract form requires close collaboration between the project partners from the very beginning. The engineering and construction work is being done more or less in parallel, using BIM.”
“The BIM model facilitates quality communication throughout the whole process,” Ring points out. “You obtain a closer and qualitatively more confident collaboration between the players. In particular, the design model makes it much easier for us to get access to construction data and drawings in order to get the construction process progressing well. It is imperative for a turnkey contract to have such a close collaboration.”
“In this contract it is ÅF that provides a complete Quadri model of the project as a basis for our construction work. As a rule, ÅF exports the data as a construction document, but I can also access the model and retrieve construction data myself from the model; a much timesaving way of working.”
“This is the first time I have used Quadri, but I've been working a lot with Novapoint and Vips data earlier on,” continues Daniel Ring.
“In particular, the Quadri model makes it very useful to view and study the design in detail, and to see if I get the same results on my side. This is perhaps the biggest difference – and a big advantage. I see what the design engineer sees. We can talk and discuss around the same thing. And when I myself retrieve measurement data from the model, it is very easy to export exactly what I need.”
"This flexibility to see and understand the entire project, and how it is progressing in all disciplines, is a huge benefit," Ring says.
"Inevitably, the data do not match hundred percent in all exports, so from time to time I have to make corrections manually, but the benefits definitely outweigh the disadvantages. Having said that, I expect Trimble will fix the issues in coming software versions. There are always new improvements coming up.”
Clarifies and streamlines
"When I myself can access the Quadri model, it is much easier for me to see how things are related. And it is much easier to retrieve real measurement data in this way. Traditionally there can be a lot of discussion with the design engineer about what data I want and how they should be. When I myself can retrieve what I need, when I need it, it's very effective and useful. All disciplines are included in the model; both rail, road, water/sewer, land work, walls, platforms, etc. It is a very detailed model,” emphasizes Ring.
“Also, the whole rail track is quite well visualized in Quadri, but not everything is equally detailed of course. There are bridges and buildings for example that need less visualization. We are looking forward to Trimble coming up with functionality to include SketchUp models in Quadri. Then we can build simple models of special objects ourselves to get even better visualization,” he continues.
"We also use the model to discuss issues and challenges in our different project meetings, including design meetings and meetings with the project owner. The model is an excellent visualization tool for achieving good communication, discussion and consensus in meetings.”
“Furthermore, the model makes it much easier to detect and correct cross-disciplinary collisions and design conflicts in the engineering phase. Hence you may avoid building errors at the construction site. This may also be a potential gain for the end-result,” concludes Daniel Ring.
Finished summer of 2018
The project status at the time of writing (April 2017) is that the railway stretch west of the tunnel is largely completed. Likewise are most large shafts and bridges. What remains is a part of the 2,9 km long tunnel, plus some work connecting to it. These are the priorities right now. Everything is supposed to be completed in June next year.