Overview
Stainless steel is versatile in various applications for its great corrosion resistance, formability and low maintenance requirements. It comes no longer as a surprise when stainless steel finds its way to tunnels. This week let us explore stainless steel application in tunnel constructions.
What is a Tunnel?
Tunnel is a man-made underground passage, constructed for efficient traffic flow of people or/and vehicles. Just like any other infrastructures, tunnels constitute a significant part in our daily life, especially in modern world.
Tunnels can be built through a mountain, under a sea, river, road, or a building. They can be quite short, such as Shimen Tunnel in Shanxi, also the earliest artificial tunnel in China, spanning only 13.6 meters. They can also be built exceptionally long, illustrated by the 57.1-kilometer Gotthard Base Tunnel, also the longest tunnel worldwide so far.
What is the Good of Stainless Steel in Tunnel Constructions?
Stainless steel is used in tunnel construction mainly for the harsh conditions where other metals can hardly compete in economic benefits.
First and foremost, stainless steel comes naturally on top of the list when corrosion resistance is a primary concern. Actually, all tunnels are expected to be operational with least maintenance for decades, some of which can be designed with a service life of 100 years. Whether for austenitic stainless steel 304L or 316L, or duplex stainless steel 2205, they can meet the timeless requirement, with grades depending on the conditions inside the individual tunnel.
Secondly, stainless steel features great formability. Tunnels are always dome shaped, so good formability saves cost and labor in tunnel construction. Stainless steel can be formed easily in distinctive shapes, justified by the world famous stainless steel sculptures like "Cloud Gate" and Haceros Inolvidables introduced before.
Thirdly, wear resistance is also an advantage that stainless steel possesses when it comes to tunnel constructions. Whether the tunnels are built for road vehicles or railway trains, they are subjected to fatigue wear. Stainless steel is durable material with high strength, which is suitable for long-term use without deformation.
Fourthly and lastly, stainless steel is fire resistant, which can be ideal material in both visible and invisible applications in tunnel constructions, with the former being fire doors and barriers and the latter reinforcing parts and failure-proof fixings. Using stainless steel can greatly enhance the safety of tunnel operation and minimize the unexpected disruption or closure of the tunnels.
The Case of Tunnel de Sartrouville in France
The rail underpass renovation project in Sartouville, France completed in 2011 can be such a representative case of stainless steel in tunnel application for the beautiful and innovative design. According to ISSF (2025), there were roughly 85 tons of 304L, 2B stainless steel sheets used as the cladding panels.
Architects EXIT Paysagistes, Bordeaux were responsible for the refurbishment of Tunnel de Sartrouville. They chose stainless steel as the cladding material inside the tunnel, which finish could reflect the floor lights, providing basic illumination day and night with aesthetical appeals.
Inspired by the Milky Way, the architects designed 400 stainless steel panels with 100 distinct embossed patterns to cover the tunnel interior. The supporting structure consists stainless steel rectangular hollow sections fixed mechanically to omega sections. All the materials were homogeneously stainless steels to keep from the corrosion that would generate from humidity and exhaust gases.
Stainless Steel from CIVMATS China
If you are looking for stainless steel sheets or/and hollow sections from China as cladding material, as in the case of Tunnel de Sartrouville, please don’t hesitate to contact CIVMATS.
CIVMATS specialize in stainless steel materials ONLY. Shapes range from stainless steel sheet plate coil strip to bar pipe wire & ropes. Choose CIVMATS, choose reliability and safety from China. Welcome for your enquiry and purchasing.
