From start to finish, collaboration is vital to the success of every construction project. This was especially true as 50 stakeholders worked simultaneously on the same model during the design and construction of the largest university hospital in Finland, HUS Helsinki University Hospital.
Named after its bridge-like structure that will connect it to two existing hospitals, the Bridge Hospital is a four-year project that began in 2018. Once complete, it will unite the operations of Töölö and Meilahti hospitals as one consistent unit to improve efficiency and streamline patient treatment.
The Bridge Hospital and three linear accelerators’ project is valued at approximately 303 million euros, encompassing an area of circa 71,500 m2 in total and net volume of circa 360,000 m3, and requiring more than 8,000 precast units and more than 4,000 tons of steel.
This project includes numerous technically-demanding structures for the hospital’s most critical operations such as intensive care units, operation theaters and X-ray units, the details of which also increased the complexity of the models. The hospital’s location in a high-traffic area, and its need to connect to existing structures without disturbing daily operations posed additional challenges.
Real-time Collaboration Across 50 Stakeholders
Constructible BIM has played an important role throughout the design process, both in helping project stakeholders visualize the design and coordinating across disciplines. The physical size of the new hospital is massive, requiring collaboration and coordination across numerous teams, including 562 sub-contractors.
Using Tekla Model Sharing for collaboration, teams have been able to work on the same model at the same time, with or without internet connectivity. As many as 50 stakeholders have worked simultaneously in the same model without the risk of clashing.
The BIM coordinator combined approximately 200 sub-models representing 16 different design fields and exported the models as IFC files for coordinating design with other project teams. The combined site/production-models act as visualization aids for teams on-site and are updated as changes are made to the sub-models so that everyone is working from the same information.
BIM is also being utilized for scheduling the building frame. On the ward floors that have repetitive rooms, indoor schedules are managed using a paced schedule which is imported into the model. Also, the project is using the Last Planner System, a collaborative planning process that involves trade foremen or design team leaders (the last planners) in planning in greater detail as the time nears for the work to be done. With this process, modeled designs are being used to coordinate installations, check for clashes and create site layout plans via mobile devices.
Open BIM for Overcoming Challenges
Connecting the hospital with the existing structures required careful coordination. One of the floors involves several hundreds of meters of connecting surfaces with the old hospital building, which was modeled based on as-built measuring to help coordinate the structures. In addition, hospital fixture procurement will be determined in a later phase, requiring structural designers to prepare for various alternative solutions.
AINS Group, which is the lead designer and delivering the structural design and detailing, and Peikko Group, responsible for steel frame fabrication and Deltabeam detailing, collaborated by working from the same Tekla Structures model.
“We agreed that the best option was to have Peikko join our model for Deltabeam design and production,” said Aleksi Jutila, project manager at AINS Group. “The precast concrete fabricator was able to take the information from our 3D model for production. Even when precast element measurements vary, they use the same type of detailing and reinforcing. We automated their modeling and drawing output in Tekla and managed to reduce the time spent on drawings from 70 percent to 10 percent. At the same time, the number of mistakes decreased and the quality of drawings improved.”
Exceptionally Detailed Modeling
Rather than treating the design and construction phases sequentially, the demanding four-year completion goal required teams to begin construction while the design process is still ongoing, making detailed modeling central to success.
Room plans were created almost exclusively by modeling. All building service systems including terminals, electrical outlets and even furniture, were modeled and included in the projections. MEP and structural design models have been used as a reference in architectural design, enriching the architectural model.
The Hospital’s large glass walls and roofs, and post-stressed shaft units, as well as requirements for operating rooms and X-ray units, added to the complexity of the models. The hospital’s steel-framed quiet room with elaborate curved geometry was modeled using the Grasshopper-Tekla link which enabled algorithmic modeling for Tekla Structures.
The level of detail in the Tekla Structures model made it possible to address these engineering challenges and connect the new hospital to the existing structures. “The connections between the existing hospitals and the Bridge Hospital are all on different levels and at oblique angles,” said Jutila. “It would not have been possible to create the new hospital without 3D modeling.”