PORT PLANNING, DESIGN AND CONSTRUCTION

AMSTERDAM PORT: BUILDING THE LARGEST SEA-LOCK

Rob Gordijn, Stakeholder Manager, OpenIJ, ,

At the mouth of the 27-kilometre-long challenges, because stability and operation DELICATE CONSTRUCTION Canal, or Noordzeekanaal that of the locks must be guaranteed. The The lock complex has a complicated soil profile links Amsterdam and its port with the sea, extremely tight construction site adds due to its history with liquefactions and major consortium OpenIJ is building the world's further complication coupled with all current breaches. Rijkswaterstaat has undertaken largest sea lock. functions like Shipping, primary water extensive ground investigations as part of The new lock, commissioned by the defense, public road and the people living the preparation for the project. An analysis executive agency of the Ministry of and working on or near the lock complex. of possible construction methodologies Infrastructure and the Environment Continuous operation of these locks and research of expected impact of the Rijkswaterstaat, will be 70 metreswide, 500 has to be guaranteed during construction foundations on the existing structures has metres long and 18 metres deep. A new of the new lock, thus requiring a lot of resulted in constraints for the construction larger lock will improve accessibility to the consideration for the impact of construction of the new lock. This was translated in the and strengthen the on the existing locks and shipping lanes. contract as restrictions to the horizontal and economy of the region by offering a tidal That is why construction commenced with vertical deformation at the top of the existing independent access for vessels constantly dredging 900,000 cubic meters of sand and locks, limitation of allowed vibration of the increasing in size. The new sea lock will temporary transporting it to the North Sea existing structures and limits on ground water replace the Noordersluis. This replacement to provide a new fairway for those ships levels and groundwater pressures near the is necessary because after being in use passing through the Middensluis. existing locks. for nearly a century, the Noordersluis is After the fairway was shifted, construction With the obligations to monitor at the end of his life term. The new sea of the new lock started. First, sheet piles deformations and ground water pressures lock should be in continuous operation no where placed in the former fairway. Then the in real time, it is possible to construct the later than late 2019. The new sea lock will sand that had been dredged was transported new lock at the prescribed location with a become the largest lock in the world in lock back to the lock complex to create a building minimum risk of failure of the existing locks. chamber dimensions. It will be located on site and a quay for construction equipment OpenIJ has carried out further research in the lock complex IJmuiden between two and materials. During construction all order to determine the impact of the selected existing operational locks: the Noordersluis building materials and equipment are being construction methods and to validate the and Middensluis. Building the new sea transported over water due to a lack of design. Field trials were undertaken to validate lock in close proximity to these locks offers space at the lock complex. the prediction models used for vibration and

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settlement. The validation models make it possible to take effective mitigation measures, which include decreasing embankment slopes, installing rock layers and drainage.

BUILDING METHODS The design of the OpenIJ is characterized by a number of methods which were chosen to minimize the impact on the existing locks and the surroundings. OpenIJ applies the vibration-free diaphragm wall method for the construction of the chamber walls as much as possible. The walls of the new lock are primarily constructed as anchored diaphragm walls. The construction method has a lot of under the structure is adjusted accordingly to to IJmuiden in 2018. After their arrival, the advantages compared to steel combi-wall maintain verticality. gates will be fitted. When construction of or sheet pile walls with respect to sound At the end of 2016, sheet piling and tubes the gate chambers is finished, the new gates nuisance and the stability of the existing locks were installed to create the cofferdams for will be placed inside the lock and the current and the primary flood defence. the construction site of the gate chambers. functions of the lock complex, water defence, Diaphram walls are constructed in a To construct the chambers for the seaside public road, can be transferred to the lock. trench. First, guide walls are constructed just and landside gates, a dry working level At that point the remaining 2,500,000 inside the top soil. The guide walls maintain will be created inside the cofferdam at 5 cubic meters of soil will be removed in the horizontal alignment when excavating the metres below the current water level. At this entrance canals and the lock can be opened trench. During excavation a bentonite slurry elevation, the cutting edge of the pneumatic for operation. is pumped into the trench to maintain caissons will be built, formed by concrete stability of the trench while excavating triangles 2.5 meters high. about 40 meters deep. Once the bottom On top of the cutting edge the 4 metres ABOUT THE AUTHOR of the panel is reached, the reinforcement thick floor will be constructed, followed cage can be lowered into position. After by the lower section, comprised of up-to- Rob Gordijn studied Ecology at the positioning the reinforcement cage, the 7-metres-thick walls. This first part of the University of Groningen and started bentonite slurry is replaced by concrete by caisson will be lowered by 5 metres by the working as Permits coordinator. using of vertical pipes. pneumatic caisson method. After reaching After several positions in permits and The new lock will be operated with this depth the second stage of the walls is stakeholder management he became rolling steel gates that are parked in a gate constructed and the structure is than lowered Stakeholder manager at OpenIJ. As a chamber when the gate is in open position. another 13 metres to its final depth. Use of Stakeholder manager he is the linking pin The upper lock head (seaside) will have the pneumatic caisson has the advantage of between the contractor consortium OpenIJ one gate chamber, the lower lock head avoiding a building pit with heavy combined and the residents en companies in the (landside) will have two chambers; one walls, heavy supporting frames and an IJmuiden surroundings. for the operational gate and an additional anchored underwater concrete floor. By doing The design of the lock started in chamber for a spare gate. The concrete so vibrations and noise could be reduced as September, 2015, the construction started structures holding the gate chambers much as possible. in 2016, and the lock should be operational have an area of 80 x 26 metres and 80 by the end of 2019. The new generation x 55 metres and a height of 30 metres. WATER DEFENCE SYSTEM ships, including cruise ships, can enter the These gate chambers will be constructed The lock complex in IJmuiden as a whole ports of the Noordzee region including on ground level and installed using the fulfils the function of primary water defence. Amsterdam through ‘this majestic door’. pneumatic caisson method. This method The new sea lock is therefore part of this has major advantages when compared primary water defence. As part of the ABOUT THE ORGANISATION with a traditional building pit with struts contract with Rijkswaterstaat, amongst other and an anchored under-water concrete things, it provides adds robustness to the The executive agency of the Ministry floor with respect to nuisance and the flood defence system. OpenIJ created this of Infrastructure and the Environment, stability of the existing locks. Where sheet additional robustness by using the flood Rijkswaterstaat awarded the contract to piling or combined walls are necessary and defence height of 7.8 metres NAP for both the combination OpenIJ. The contractor the impact on the existing locks would be the seaside and landside gates and applying consortium OpenIJ, consisting of BAM- too large, sheet piles will be applied in a walls along the lock chamber with a retaining PGGM and VolkerWessels and DIF, is cement-bentonite slot and tubular piles for height of 8.85 metres NAP. As one gate will responsible for design, build, finance and a combined wall will be drilled. always be closed, there will also always be maintenance (DBFM) during 26 years of Basic principle of the caisson method is to a closed flood defence, even in the unlikely the new sea lock. The IJmuiden sea lock create a pressurized chamber underneath the event that the seaside gate cannot be closed is one of the so-called Connecting Europe structure. The air pressure helps to keep the during a storm surge. Faciliting (CEF in short) and is partly water out of this chamber. From this chamber, The lock gates will reach almost 8 meters financed by the EU’s CEF programme. the soil under the structure can be removed. above the current water level, thus providing By carefully and evenly removing the soil defence against rising sea levels while also ENQUIRIES from under the structure, it will submerge strengthening the country's flood control. The gradually until its final depth. During this enormous lock will be cast from 290,000 cubic Rijkswaterstaat: [email protected] process verticality is monitored continuously meters of concrete. The lock gates are being OpenIJ: [email protected] and the place where the soil is removed from built in South Korea and will be transported

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