Case Pedestrian Bridge at TRUMPF Headquarters

Courtney Tenz

Challenge

Connect two main facilities at the TRUMPF Headquarters with a corrosion-resistant pedestrian bridge over a heavily trafficked street that is close to a busy interstate highway and subject to icy conditions in winter.

Solution

The Outokumpu Forta DX 2205 stainless steel used in the minimally designed bridge is cost-effective and corrosion resistant.

Delivery

Steel grade: Laser-cut Outokumpu Forta DX 2205

Footbridge safely connects TRUMPF employees

A family-owned company that dates back to 1923, TRUMPF has become a world leader in industrial laser technology and the manufacture of machine tools used in flexible sheet metal processing. With over 12,000 employees in locations around the world, the company maintains its headquarters in a campus spread-out in Ditzingen, a green suburb of Stuttgart, Germany.

As demand for their technological expertise and machine tools has grown, so have the facilities in Ditzingen. There, employees produce 3D laser printers, a variety of laser systems and components for machine tools in buildings that spread across several city blocks.

 

Connecting employees on campus

Bisected by the heavily trafficked Gerlinger Strasse, the campus at TRUMPF has become a lot easier to move around beginning in July 2018, when a pedestrian bridge connecting the two main facilities has been put into service.

The 28 meter long bridge is designed by schlaich bergermann partner and manufactured by Franz Prebeck GmbH &Co KG. Due to the high efficiency of the supporting structure the lightweight shell structure could be made of only 20 mm thin, double curved Outokumpu Forta DX 2205 stainless steel sheets. Specializing in artistic steel constructions, schlaich bergermann partner ensures creative architectural designs, and maintain unique bridge characteristics and aesthetics.

 

One-of-a-kind cutouts

Using Forta DX 2205 as the primary material in the bridge’s construction is ideal not only due to its cost-savings. In southern Germany, where wintery conditions and the use of salt on roadways to combat ice can lead to corrosion quickly, the durability and corrosion resistance found in Forta DX 2205 is a necessity.

“We selected Outokumpu duplex for its corrosion-resistant properties, as the roadway below sees a lot of traffic and it needs to stand up to the road salts and icy conditions in winter,” said Florian Prebeck of Franz Prebeck GmbH & Co KG.

In choosing duplex, the bridge design is likewise reduced to a minimum, providing it with a modern aesthetic. Thanks to a high standard of efficiency, engineers were able to employ double-curved stainless steel sheets as thin as 2 centimeters, stabilized by upstands which turn toward the footings and form triangular bearing points.

With a lightweight shell structure, the one-of-a-kind pedestrian bridge also serves as a showcase for TRUMPF laser technology. The steel sheets provided by Outokumpu for use in the bridge were cut to shape using TRUMPF laser machines at Outokumpu’s service center in Aalten, The Netherlands; cutouts had to be delivered with a BrightLine cut quality.

“We appreciated the smooth cooperation with Outokumpu that ensured the steel was delivered on time and cut to spec,” said Florian Prebeck.

Because pedestrians will be walking directly on the stainless steel shell, the steel has already been treated to avoid slippage and includes small holes bored at a maximum of 1.5 cm apart. To respond to flux, engineers intend to laser openings into the sheets that are orientated according to how the structure will be used.

After around six months construction period the bridge has been completed in June 2018.

Recommended products and insights

How to build a bridge that saves a fortune

Our expert Andy Backhouse explains how the right grade of stainless steel can create a structure that resists corrosion and minimizes maintenance needs over a typical bridge lifetime.

Stainless steel for bridges

Bridge projects are in a class of their own – just like Outokumpu stainless steel. Marked by harsh environments, heavy lifetime usage and high aesthetic expectations, bridges demand special considerations upfront if they’re to go the distance.

Forta

The Forta range contains duplex and other high strength stainless steels that enable thinner structures and weight reduction (measured in Rp0.2 > 400 MPa. PRE 16 to 43).

Quarto plate

For extra thickness or larger dimensions, Outokumpu hot-rolled plates – quarto or heavy plates – are the ideal solution. Because Outokumpu oversees production from melt to market, superior quality and on-time delivery are assured.

Corrosion resistance

Corrosion is the gradual degradation of a metal by a chemical, often electrochemical, reaction with the surrounding environment. It impacts material properties such as mechanical strength, appearance, and impermeability to liquids and gases.

Recommended reading

Article

What if bridges were built to last?

Case pedestrian bridge

Spanning time and distance

Article

Home of Rioja wine toasts sustainable stainless steel footbridge

Case Stockholm railway bridge

Upgrading bridge construction

Case Södertälje bridge

Designed to last

Case Story

The ultimate cliffhanger - The Gap

Article

Duplex in bridges and structures

Article

Sustainability is driving the adoption of duplex steel

Article

A bridge designed for manufacture