Rotterdam – Koninklijke Boskalis Westminster N.V. (Boskalis) and Van Oord Dredging and Marine Contractors B.V. (Van Oord) deliver the first stage of Maasvlakte 2 to client Port of Rotterdam Authority on 17 April: on schedule, on budget and in accordance with the quality requirements specified. PUMA, the joint venture of the two contractors, started the expansion of the port of Rotterdam five years ago. Today the realisation of 700 hectares of new industrial sites, 11 kilometres of seawall, 3.5 kilometres of quay wall, 24 kilometres of roads, 14 kilometres of rail and 560 hectares of port basin is a fact.
Maasvlakte 2 not finished yet
The work now completed by PUMA is the lion’s share of the construction of Maasvlakte 2. The Port Authority is currently working on the nautical accessibility of Maasvlakte 2; the installation of leading lights and buoys for shipping will enable Maasvlakte 2 to be opened to ships on 22 May. In the coming year work will continue in full swing on infrastructure on the boundary between the existing port area and Maasvlakte 2, including the construction of a flyover intersection at the ECT terminal, so that the new port terminal can connect seamlessly to the existing one. In addition, APM Terminals (APMT) and Rotterdam World Gateway (RWG) are working hard on the new container terminals which both companies want to have in operation by the end of 2014.
Maasvlakte 2 is a project with big numbers: 240 million cubic metres of sand was sprayed to create land, raise industrial sites and construct 7.5 kilometres of beach and dunes. 7 million tonnes of riprap, 20,000 concrete blocks, each weighing more than 40 tonnes and 150,000 tonnes of clay were processed in the 3.5 kilometres of hard seawall. Around 300,000 cubic metres of concrete was used in the construction of the quay walls.
The Port Authority had a budget of €1.9 billion for the construction of this first stage of Maasvlakte 2 (the new land, infrastructure on Maasvlakte 2 and connections to the existing port area). The contract with PUMA is by far the largest and most striking part of the work. For this contract, with a value exceeding €1.1 billion, the Port Authority chose a Design, Construction and Maintenance contract. A Program of Requirements, consisting largely of functional requirements, specifies the design, realisation and maintenance. This allowed Boskalis and Van Oord to demonstrate their innovative added value. In collaboration with the client, the design of the hard seawall was optimised as a stony dune with a block dam in front of it as a breakwater. The gale which this innovative seawall should be able to resist occurs in statistical terms only once every 10,000 years. Scale testing demonstrated the real effectiveness of the design prior to construction.
To contractors and client safety was of paramount importance. More than 2,000 people worked around 6 million hours without any accidents involving permanent injury.
PUMA developed a special crane to build the block dam: the Blockbuster. This 1,200-tonne equilibrium crane could place a 50-tonne burden 63 metres from the heart of the mobile undercarriage. Within one and a half years experienced crane operators placed almost 20,000 blocks of 2.5 cubic metres with a precision of 15 centimetres.
Floating cranes used a specially designed ripper grab to pick up the concrete blocks and buckets to collect the riprap from the old block dam. The recycled material was stored, ready to be worked into the new block dam.
Boskalis and Van Oord used dozens of trailing suction dredgers, cutter suction dredgers, stone dumpers, backhoes, bulldozers, dumpers and various other kinds of equipment over the past five years. At the height of the sand work in the spring of 2010, there could be up to 12 trailing suction dredgers working at the same time. 3.8 million cubic metres of sand was extracted and processed in the reclaimed land in one single week. This was a world record for the amount of sand extracted at sea which had ever been transported to a single project by trailing suction dredgers.
10 years of maintenance
The contract includes a maintenance period of 10 years. Boskalis and Van Oord have undertaken to keep the entire seawall at optimum strength until 2023. Similar to the entire Dutch coastline, sand will also have to be added here to the soft seawall. Following every severe gale, the hard seawall will also be inspected and, if necessary, the cobble beach will have to be replenished.