IJboulevard: complex hydraulic engineering project in an A-location

On the IJ side of Amsterdam CS station, Van Hattum en Blankevoort is building the IJboulevard, a complex hydraulic engineering project at an absolute prime location. A bicycle storage facility with space for 4,000 bicycles will be built under the water in the IJ, while a new piece of Amsterdam will rise on top of the facility, which will be designed as a residential area with a pedestrian promenade.

The City of Amsterdam wants to hide parked bicycles from view as much as possible. The existing floating bicycle parking facility and deck barges on the IJ side of Amsterdam CS are therefore making way for an underground alternative. A very special and above all technically complex alternative. The IJ behind Amsterdam CS is one of the busiest waterways in Europe. On top of that, the North-South line also crosses the IJ at this location. A challenge that Van Hattum en Blankevoort, according to environmental manager Rob Gordijn, has taken on board. 

Puzzle

In the tender, the City of Amsterdam, together with the Municipal Department of Metro and Tram, set strict requirements regarding the relocation, in part because of the North-South Line. "The maximum allowable deformation on the existing structures is 6 millimeters, both during construction and later during operation," Gordijn said. "The North-South line is in the ground; we are building the bicycle parking facility on top of it. Foundation piles are needed to support the parking facility, and installing them involves a certain amount of displacement. So we had to contain that displacement. This was a puzzle we solved during the tender phase and helped us win. In addition, sustainability was obviously an important factor in the design in terms of the MKI. But we also considered how we could add additional functions below the waterline to promote ecology and habitat for fish. We scored on that too."

Pre-construction site

Ultimately, the solution is a combination of factors. "Important in this is that we pre-built the bicycle parking in three elements of about 80 by 25 meters in the Western Docklands," Gordijn says. "This way, we did not have to make a construction pit on site and fewer foundation piles were required (a total of 72 tvsi piles), because of the lighter construction. This significantly reduced the influence on the subsoil, and the lighter construction also resulted in a lower MKI. Moreover, we could work simultaneously on the foundation at the project site and the final concrete construction at the preconstruction site. So in terms of planning, it was also very efficient. Last fall, the three elements were immersed on site and joined together to form one large container. In the water in front of these elements we are also constructing a free-standing approach barrier, which will protect the existing quay and the bicycle shed from possible collisions with the (busy) shipping traffic on the IJ. Almost all work and construction logistics will be carried out from the water. Road users and local residents will have little to no inconvenience from the work."

Currently, Van Hattum and Blankevoort is completing the completion of the parking facility, building the ground level entrances and also the first signs of paving on the 6,000 m² large promenade are slowly becoming visible. Completion is scheduled for the first half of 2023.