Harsco was able to design and construct an innovative, bespoke support girder system which overcame the restrictions of the site and allowed the construction of a number of key structural elements of the new building.
The new theatre in Bordeaux, France, is being built on a site surrounded by existing buildings. Harsco was asked to provide a support system to carry formwork for the construction of a number of 6 ft wide, 7 ft high, 105 ft long in-situ concrete beams. These beams needed to span the stage area and also support a further 5 floors of apartments and office accommodation being built above. The girder systems supplied by Harsco were to vary in length - with the longest being 30.90m - which needed to be lowered, relocated, and in some cases altered in length before work on the next beam could begin.
Working on behalf of Portuguese contractor BUILDIN, Harsco was able to draw on its wealth of technical expertise and devise a bespoke H33 braced truss-girder system which was sufficiently flexible and reliable to satisfy this demand. The Harsco H33 beam system offers a flexible, robust and reliable solution with the high load-bearing capacity needed for this type of project. Its excellent weight-to-capacity ratio made it ideal for the long spans involved, while the easy to assemble nature of the system components ensured rapid construction of the girders required.
This proved to be a faster, more cost-effective and practical solution than other alternatives which might have been used. However a severe lack of working space on the site meant that Harsco also had to adapt the traditional methods used to construct such a system.
“We actually did much of the construction work on the girders about 10km away from the site itself," explains Harsco’s Ingo Schnelting. “This meant that we could prefabricate the girder sections under more controlled conditions, which made it far easier to ensure that they complied fully with the drawings. That way we were able to avoid any unexpected problems on site and be confident that the girders would fit neatly into place.”
Harsco was then able to partially dismantle the girders for transportation and deliver them to site. This also minimised the disruption to other trades that would have been caused by fabricating the units on the site itself. Lack of on-site storage space meant that Harsco had to adopt a just-in-time schedule for these deliveries and also co-ordinate this with special permission from the city authorities to operate extended length transport vehicles.
“We had to remain flexible in our approach to every aspect of this project,” adds Ingo Schnelting. “The different lengths of concrete beam that the building required meant that we sometimes had to remove the girders from the building and transport them the 10 km back to the construction area. There we were then able to re-configure their length before delivering them back to site and using hydraulic jacks to raise them into place, ready to support the formwork required to make the next beam.
“This was an excellent example of Harsco’s ‘Insight onsite’ philosophy in action and illustrates the way we are able to develop bespoke solutions that are tailored to the specific requirements of individual projects,” adds Ingo. “The end result of this approach is that we can deliver the highest standards of reliability, cost-effectiveness and safety and that was certainly the case on this project.”