OP-Pohjola headquarters

Sweco Rakennetekniikka (Finnmap Consulting Oy), Sweco Talotekniikka Oy, JKMM Arkkitehdit Oy, Granlund Oy, Haahtela-rakennuttaminen Oy, Byggnadsekonomi Oy

OP-Pohjola Vallilla 2015 project is located in Helsinki, Finland. Project included demolition of old buildings, construction of a new building on the location of demolished buildings and also renovation of some old buildings. Area of the new building together with a glass roof is about 58.000 sq m and the renovated area is about 30,000 sq m. Built  and renovated buildings will be used as office space. Project consists of 4 underground floors and 7 floors above ground.

Buildings are founded on solid rock. Foundations are about 12 meters below groundwater elevation and because of this all the rock excavations and ground structures were made waterproof. Underground floors are used for parking. The structure of underground floors consists of post-tension cast-in-place. Load bearing structures for floors 1-7 were done with composite columns, WQ-trusses and beams with hollow core slabs. The geometry of building is very diverse and versatile with a lot of structures sloped and skewed. The whole structure has been stiffened with elevator- and stairwells. Facades  include precast elements and glass structures. Surface of precast elements was designed to have varying surfaces of rock and plaster. The area between the new building and the renovated buildings was covered with complex geometry glass roof.

The whole structure of the new building was modeled. Modeling included main structures, embed objects in cast-in-place and precast concrete, also reinforcements in foundations, shelters, elevator and stairwells, slabs and composite columns. Precast elements were also fully detailed. Reinforcements list and other reports were created from the model and given for use to general  and subcontractors. Also the renovated areas were modeled and utilized in design process.

Hole-reservation process between MPE/HVAC and Structural designer was handled using BIM tools. The model consists of about 7000 void objects and based on those structural designer created necessary hole-reservation drawings semi-automatically.

The design statuses were updated to the model, which enabled contractors and other designer to follow design progress.
The geometry of the new building is very complex and demanding from the structural point of view. Sloped and skewed structures caused huge forces, which caused interesting challenges for structure and connection design. The geometry of facades included sloped and skewed folds, leading to very unusual precast elements with fold in middle of element.

The multi-material project has been modeled simultaneously in different locations. Facades were created in  a separate model purely because model size. Skewed, sloped and chessboard-like facade has made handling of geometry and connections were demanding. Large glass roofs created with steel structures have really out of ordinary geometry and also long span.