Strolling over Mediterranean breezes

Challenge

Exposed to sea spray, the Águilas footbridge had to be corrosion-resistant. Located over a seasonal watercourse, it required a light, strong material.

Solution

Outokumpu Forta duplex stainless steel was chosen for the structure because of its superior resistance to corrosion, low maintenance costs and aesthetic possibilities.

Delivery

Steel grade: Outokumpu Forta DX 2205

The coastal town of Águilas, in southeastern Spain, welcomes the light of the Mediterranean with open arms. Its bay captures the sea breeze as the sun paints the waterfront in warm hues.

Until recently, people enjoying the seaside promenade could not walk directly from the centre of town to the marina, separated by a ravine. A stainless steel footbridge now connects these two neighborhoods, crossing the 35 meters above the Cañarete watercourse.

 

Project on two conditions

Acuamed, a state-owned enterprise, had two key design requirements for this project.

First, the footbridge had to be durable. “It is constantly exposed to the sea breeze, which is very corrosive and quickly causes micro-perforations and rust,” explains Fernando Villalba, Engineering and Construction Director at Acuamed. “This could result in structural problems and high maintenance costs.”

Second, the structure had to be light, yet strong. “We were looking for a footbridge with little visual impact on the surroundings,” says Villalba. The watercourse below may carry large amounts of rainwater, so the bridge had to span the entire width of the ravine without any middle support.

 

Low-maintenance and good looking

At first, carbon steel and wood were considered as possible materials, but Acuamed chose duplex stainless steel because of its superior resistance to corrosion, low maintenance costs and aesthetic features.

“Duplex is a material that can withstand outdoors exposure for many years,” notes Villalba. Engineers tested different types of duplex grades until they settled on Forta DX 2205. “The technical department of Outokumpu recommended Forta DX 2205, based on their previous experience,” recalls Villalba. “We are happy with the choice of this material.”

Forta DX 2205 also solved Acuamed’s need for a lightweight structure. “A different type of steel would have needed thicker, larger beams, which would have made the structure heavier and more cluttered,” says Villalba.

 

Outokumpu goes the extra mile

Outokumpu’s support was frequent through the life of the project, according to Villalba. “Whenever we had questions, they solved them promptly.”

Outokumpu delivered custom-cut sheets straight from the factory to a local workshop. The footbridge was fully assembled offsite, then transported by road to its final location. When Acuamed found signs of rust on the handrails, made out of 316L steel from another manufacturer, “Outokumpu collaborated in solving the issue and finding the origin of the corrosion,” appreciates Villalba. “The experience has been very positive.”

Watch a video of the construction of the bridge: https://vimeo.com/151710391

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