Old-style renewed

mageba’s team in Germany shows it has what it takes to renovate expansion joints of any kind – even the old-style roller shutter joints still in use on older bridges throughout the country.

An ongoing project to renovate a number of bridge structures on the B327 highway in western Germany, where it crosses the Rhein in Koblenz, has presented a number of challenges to date – but nothing that our local expansion joint experts couldn’t handle. They have proven their ability to efficiently install TENSA® MODULAR expansion joints to replace existing modular joints on numerous occasions, including using cleverly developed methods that minimise impacts on the structure and on traffic – and on this project they have already installed specially designed “hybrid” modular joints to replace the joints of another manufacturer. However, the bigger challenges relate to the “roller shutter” expansion joints that were used when the structures were constructed fifty years ago. It was concluded by the responsible engineers that some of these, at one end of the main bridge over the Rhine, should be taken apart and renovated using the existing roller shutters, while others, on highway access structures, should additionally receive new roller shutters in the course of the renovation.

The roller shutter joints of the Rhine bridge were originally expected to require only minor repairs, but the true extent of their deterioration became evident when the first roller shutters were removed. Fortunately, mageba’s local engineers were able to quickly develop a much more extensive renovation concept to address the deterioration. The roller shutters have already been mostly renewed, with all removable parts replaced or made “as good as new” in the factory.

Meanwhile, planning has been progressing for renovating the access structure joints, with newly fabricated roller shutters based on the original design drawings from five decades earlier. This required skill and experience in understanding the design detail from the old manually created drawings from the pre-CAD era, and transforming these into the type of CAD drawings that today’s engineers and fabricators are used to using. In doing so, of course, the much advanced design standards and specifications that apply today also had to be considered.

We are glad to have been given the opportunity to contribute to this special project, which enabled us to draw from our vast experience in the design, fabrication and maintenance of all kinds of expansion joint. And we are always happy to support sustainable bridge construction and maintenance in every way possible – minimising the need to repair and replace, through the high quality and durability of our products, and optimising renewal and replacement works when they become necessary, by renovating and renewing existing elements where feasible.

Bridge designer: Georg Strigl
Contractor: Schnorpfeil Treis Karden
Bridge owner: Landesbetrieb Mobilität Koblenz

The B327 highway bridge over the River Rhine in Koblenz, western Germany was built five decades ago with roller shutter expansion joints – a type of joint that was widely used in Germany at the time

© Holger Weinandt

Specially designed “hybrid” TENSA® MODULAR expansion joints have been installed at two locations to replace the existing modular joints of another manufacturer that have not performed as well as expected

View of the existing roller shutter joint at one end of the Rhine crossing, before the renovation of this joint commenced

Following removal of the first roller shutter elements, the true condition of the expansion joint could be properly evaluated from beneath – and it was found to be in need of a much more thorough renovation than previously believed

View of the joint following removal of a number of roller shutter elements

A roller shutter element in mageba’s factory in Göttingen, Germany, following disassembling, renovation and application of new corrosion protection

View of the joint after renovation of the substructure, including replacement of bearings etc., with the first fully renovated roller shutter elements put back in position

Lifting of the last roller shutter element into position on this side of the structure

When all roller shutter elements have been positioned, the shorter sliding plates can be installed on top, connected to the superstructure at the opposite side of the bridge’s movement gap