290 tons of steel support structures

The steel support structures (temporary gantry structures) for the realization of two viaducts (C and D) of the Rozenburg interchange, part of the Blankenburg connection, come from the hand of Ferross Staalbouw. "We handled the engineering, detailed calculations, fabrication and assembly and disassembly of the structures," says Mark van den Heuvel, head of project management at Ferross Staalbouw. "In total, some 290 tons of steel will pass through 'our hands' for a year and a half."

In November 2019, Ferross Steel Construction began engineering work. "During the work, all steps are coordinated in close and pleasant cooperation with BAAK. Everything is discussed down to the detail level," says Van den Heuvel. "The added value we offer lies mainly in the enormous knowledge we have in the field of producing, assembling and dismantling the necessary steel structures. By thinking along at an early stage, we have arrived at professional and workable solutions to complex issues." Ferross is certified according to NEN EN 1090 up to execution class EXC 3. This project is being carried out in EXC 2.

Temporary gallows construction

The superstructure, or road surfaces of the viaducts, consists mainly of precast girders. "These girders are not supported by a transverse girder, but by a column strip to be poured later," Van den Heuvel explains. "The gallows structure has a temporary function and carries the girders until the column strip is poured and cured. Our construction serves to transfer the forces to the foundation."
Both viaducts are being built in six phases and have a length of about 150 meters, a height of about 1.7 meters and consist of five fields. "The gallows structure is used on axis 3 and 4. The width of the decks ranges from 13 to 18 meters and has a
variable longitudinal ramp. According to Van den Heuvel, the biggest challenge for Ferross Steel Construction is in the disassembly. "Steel parts weighing about 8.5 tons have to be removed. These are located several dozen centimeters below the upper deck. Due to a pipeline route between piers 3 and 4, there is only a few meters of space to place lifting equipment for disassembly."

Reuse

For two piers, of axles 3 and 4, of viaduct D, approximately 199 tons of steel were fabricated, delivered and assembled by Ferross. Assembly took place in March and April 2020. "Seven trucks delivered steel for these pillars in 3.5 weeks. This steel will be reused for the gallows structure of the two piers of viaduct C. About 91 tons of steel will be added to this. These piers are more than 3 meters higher," Van den Heuvel adds. An inspection by a quality inspector hired by BAAK also took place during the work. That process went smoothly and without delay for Ferross. 

Clients make a conscious choice for a steel construction. Ferross Staalbouw has all the knowledge and craftsmanship in house to come up with innovative ideas and turn them into professional designs. Ferross Staalbouw produces for governments, small and large clients at home and abroad, worldwide. Ferross Staalbouw is an important partner in the metal sector.