19 Dec 2011
The Story
48.3 Scaffold Design recently had the privilege of being invited to Layher's global headquarters in Eibensbach, Germany for an introduction to the company's new Keder XL roofing system.
As part of the trip we were taken on a tour of the impressive production facilities on-site and had a chance to see some other new products that Layher have brought to market recently. For example a 'parabolic grandstand' that increases in steepness to provide better viewing positions towards the back of spectator galleries. We also had the chance to see TG60 shoring towers and a new base component that can be adjusted for slopes of up to 16% (9 degrees) to provide a level footing on uneven ground.
The main purpose of the visit though, was to view, build and discuss the new Keder XL temporary roof system. After an interesting presentation, highlighting the advantages of the new temporary roof and the differences when compared to the old Keder roof system, we had the opportunity to discuss the technical details with Layher Germany's engineering team. We also had the opportunity to go 'hands on' with all of the new components before our tour of the manufacturing facilities.
The new roof has a stronger top chord profile (and is still the only temporary roof beam with the sheeting track integrated into the top chord, rather than fixed on separately) as well as various other strengthened components. The changes combine to give a 67 to 115 percent increase in bending capacity (depending on which bracing arrangement is used), and a 86 percent increase in shear capacity, when compared to the previous Keder temporary roof.
One other improvement is the introduction of different bracing options, reducing the quantity of bracing required for light duty / short span roofs, whilst allowing for heavy duty / long span roofs using the same roof beams. The new bracing frequencies range from 1.0 m centres for both bracing frames and horizontal stiffeners to 2.0 m centres for each member.
Another feature of the Keder XL temporary roof is the new tension bar system. This new tension bar can be fixed either directly between the support points or at any convenient point on the bottom chords of the temporary roof beams. A tension bar greatly increases the load bearing capacity (and therefore span) of the temporary roof under snow loading. In fact the maximum span of the XL Keder roof system is 40.0 m!
All in all, the facilities and staff at Layher were impressive, and seeing he production methods and attention to detail in design and manufacturing inspire confidence in the products. The XL temporary roof looks very useful and is certainly an improvement over the previous Keder roof. We look forward to designing temporary roofs with the new beams as and when our clients start to take advantage of the equipment. No doubt Layher UK's sales representatives will be busy publicising the benefits over the coming weeks and months!
