The Kruunuvuori Bridge creates a transport link between the Kruunuvuorenranta residential area on the waterfront, the island of Korkeasaari, Laajasalo, and central Helsinki. When completed, it will be one of the  longest bridges in the world built solely for public transport, pedestrians and cyclists.

The planning of the Kruunuvuori Bridge was launched in 2012 with an international design competition, the aim of which was to design a transport link from Nihti to Kruunuvuorenranta, via the island of Korkeasaari. The focus was on the design of the Kruunuvuori Bridge, which forms a crossing point between Palosaari and Kruunuvuori. Out of 52 entries, 10 proposals were accepted, including that of our international design group Gemma Regalis was selected as the winner.

 
Focus on the User Experience 

The design of the bridge took the user’s perspective very much into account, both in terms of visual appearance and user-friendliness. The aim was to make the bridge, which is over a kilometre long, light and airy, to minimize the disruptive effect on the landscape. The bridge horizontal curvature is based not only on structural reasons, but also on improving the user experience - by walking on a curved bridge, a person can better perceive the destination. The functionality and interior details of the bridge have been carefully considered to meet the needs of pedestrians, cyclists and public transport users.

The bridge is part of Helsinki’s Central Park, whose beaches are a protected area. In designing the bridge lighting, emphasis was placed on creating a subtle entity where the amount of extraneous light in the environment is as low as possible. The illuminated central pylon of the cable-stayed bridge forms a new landmark in the city. The pylon is 135-metre high and its facade lighting changes according to the time of day and the seasons. With the help of LED-coloured lights, it is possible to change the pylon’s colour, for example during the holidays.

Solutions for a Long Time

The total length of the Kruunuvuori Bridge deck is over a kilometre and the bridge superstructure is continuous between the ground supports. In the middle of the horizontal arched bridge is a sloping rope section formed by a pylon and two main sections of 260-metre. The main bridge combines two access bridges, which are continuous composite beam bridges.

A life span of 200 years has been set for the Kruunuvuori Bridge. The uniquely long life calls into question the structural design and material choices, and also creates special requirements for bridge maintenance.  A significant part of the design was to identify structures and components that are highly stressed and cannot be replaced. The long service life places particular demands on the design of the bridge’s supporting structures, i.e. steel and concrete structures.

The concrete structures in the water exchange area are the most stressed. Part of the design work included defining the product requirements for the concrete to meet the requirements for extending the service life of infrared concrete.

The durability of the bridge steel structures is ensured by careful planning and implementation to avoid possible fatigue of the steel structures. Fatigue of steel structures can be observed in long-term use, especially in joints and stiffeners. The emphasis is therefore in finding the simplest and most functional solutions possible in the design.

Seasonal variations and weather conditions were also taken into account in the design of the cable-stayed bridge steel cables. The possible accumulation of snow and ice on the cables during the winter is solved with structural solutions that prevent ice formation and ensure good maintenance.

Multidisciplinary Design Expertise

The Kruunuvuori Bridge is a comprehensive project involving a wide range of our designers. In addition to experts in bridge and structural design, and wind technology, our project team consists of experts in infrastructure design, traffic and design. The result is a maritime route that serves the people of the area, supports sustainable development, and creates even better opportunities to move around the city on foot, by bicycle and by using public transport. According to current estimates, the bridge will open to traffic in 2026.