When it comes to choosing materials, steel, because of its exceptional physical and mechanical characteristics, is the most popular amongst designers. It can be used to rapidly build economical, durable, and safe structures. The steel used to make hot-rolled sections, which can themselves be indefinitely recycled, is made from recycled scrap. It is particularly suitable for machining and shaping. However, it tends to react with agents in the atmosphere to form stable thermodynamic bonds – ferrous oxides and/or salts.

The ability of steel to revert to its natural or original state is called corrosion. In layman’s terms: steel rusts!

Suitable corrosion protection for long-lasting steel

The primary quality of steel - i.e. its ability to retain its physical and mechanical strength, or in the case of a steel structure, its load bearing capacity - is generally long-lasting and is only compromised when corrosion reduces its cross section to such a degree that safety is adversely affected.

The service life of a structure depends on the rate of reaction between the steel and its environment. These reactions depend on the nature and concentration of the corrosive agents present.

Corrosion protection of structures must therefore be considered as intervening in this process in order to prevent the reaction or greatly reduce the rate.

Large numbers of steel structures, some of them a hundred years old, which have benefited from the combination of a suitable corrosion protection treatment and regular maintenance, show impressively the potential of steel. However, these types of structures, requiring high maintenance costs, are no longer acceptable today.

New requirements govern the design of the steel structures of the twenty-first century:

•    Environmental protection policies enforced at both the national and international level have led to a considerable reduction in the amount of corrosive load in the atmosphere over the last twenty years. This has resulted in a noticeable drop in the average corrosion rate of steel and zinc as well as improved resistance of coating systems.

•    The design of steel structures is substantially improved through the effectiveness of welding procedures and the vast range of rolled sections available thus contributing positively to ensure that corrosion protection systems have long service lives. Maintenance and renovation costs continue to fall because the amount of exposed surface area has been greatly reduced and ease of access improved. The ability of new coatings to resist the stresses in their surroundings has been increased considerably. New inexpensive coating methods are employed in fabrication shops and on construction sites.

•    Zinc baths have sufficient capacity and are large enough to allow widespread hot-dip galvanisation of steel structures involving large components.

•    Combining the hot-dip galvanisation technique with adapted paint systems for zinc coatings - so called duplex systems – renders maintenance unnecessary with, in most cases, the corrosion protection not requiring any attention for the entire service life of the structure.

•    Corrosion protection is becoming an integral part of the fabrication process for steel structures.

Text: ArcelorMittal Commercial Sections
Images: ArcelorMittal Europe - Long Products, ArcelorMittal, ArcelorMittal Europe - Flat Products

Related link(s)

Corrosion protection of rolled steel sections using hot-dip galvanization

Corrosion Protection: Hot-dip Galvanizing of Structural Steel

Corrosion Protection: Hot-dip Galvanizing of Structural Steel

We value our partners. We are proud to cooperate with the companies and institutions that count on ArcelorMittal's technical know-how and expertise in their mission to create innovative, sustainable, and value-added solutions for their key markets. As our partnerships continue to grow, so has our newest Constructalia section – Partners.

Steel for construction

Our high quality steels are the perfect base for the creation of elements or finished products for use in a wide scope of the construction market. From heavy plates to organic or metallic coated coils, our production portfolio meets the highest demands in terms of resistance, corrosion protection, and aesthetics.

Meet our partners utilising our extensive Granite® range or corrosion resistant Magnelis®: Blachdom Plus, Budmat, and Regamet in their roofing solutions; BUCON for their steel tanks; Metpol with their plasterboard solutions; Meteor Systems and Zimmermann in their horticultural and agricultural systems; and InQuik for their innovative bridges.

Discover: Metal Union’s application of our metallic coated steels in their profiles, Gagnepark’s usage of sections and Cofraplus® for their multi-storey car parks, and Matière’s patented bridges with our heavy plates.

Steel promotion

From partnerships with associations promoting steel as a building material to new technologies and construction solutions with steel – and everything in between – we work closely with our partners to disseminate knowledge about steel in construction.

A new addition to our Partners section is ConstruirAcier, who inform and advise architects, engineering offices, and investors on the economic and environmental challenges faced by steel in architecture.

Text: Constructalia
Images: Blachdom Plus, BUCON, ConstuirAcier, Gagnepark, Matière, Meteor Systems, Metpol

ArcelorMittal has been recognised as a Steel Sustainability Champion for the third year running by the World Steel Association (worldsteel).

A perfect run

The accolade for 2019 maintains ArcelorMittal’s perfect run as a Steel Sustainability Champion since the programme was launched in 2017. Being named a Sustainability Champion distinguishes the steel companies who, like ArcelorMittal, are leading by example in creating a truly sustainable steel industry. The programme seeks to encourage other steel companies to increase their efforts, set higher standards, and demonstrate a strong commitment to sustainable development and the circular economy.

Dedication to sustainability

This designation reflects ArcelorMittal’s dedication to worldsteel’s sustainable development charter; the company’s regular and transparent reporting on its environmental, social and economic performance; our commitment to providing a safe and healthy work environment for steelworkers; and our success in 2019’s Steelie Awards, where the ‘Excellence in sustainability’ category was won for our Climate Action Report.

Worldsteel represents steelmakers in every major steel-producing country, as well as national and regional steel industry associations and steel research institutes.

Inventing smarter steels for a better world

Brian Aranha, executive vice president, head of strategy, CTO, R&D, CCM, global automotive, communications and corporate responsibility, ArcelorMittal said, “As the world’s leading steel company, we are inventing smarter steels for a better world because we recognise that sustainability sits at the heart of securing our license to operate, into the future. Extending our sustainability champion status for the third straight year is a confirmation of our dedication to making sustainable development a priority for our business.”

Text: ArcelorMittal Corporate Communications
Logo: worldsteel

Related link(s)

worldsteel Sustainability Champions logo

The French company Matière first introduced its Unibridge® concept in 2004. Today these patented structures are shipped around the world where they are used as permanent or temporary crossings for vehicles and pedestrians. Thanks to their modular nature and ease of construction, the Unibridge® is particularly popular in remote regions where materials and skilled workers are hard to find. The solution uses ArcelorMittal’s S355K2+N and S460M high strength steel plates which are known for their durability, giving the Unibridge® a 100-year design life.

Close cooperation with ArcelorMittal

“The close cooperation between ArcelorMittal Europe – Flat Products and ArcelorMittal Projects, together with the quality of the plates produced in ArcelorMittal’s mill in Gijón, Spain guarantees the best level of service for Matière,” says Michaël Regal, Account Manager for Matière at ArcelorMittal Projects.

Since 2018, heavy plates from our Gijón mill have been successfully delivered to Matière and its subcontractors in France, Belgium, and Portugal. “When a very short lead time is required, we are in the position to offer a delivery in less than a week at any Matière yard thanks to our own stock of plates, beams, and tubes,” says Michaël Regal.

Designed for remote and developing regions

The Unibridge® was initially developed as a solution for the military but was never adopted. Matière immediately saw the potential of the solution in developing countries and remote locations as Hervé Blanc, Deputy General Manager of Matière, explains: “These areas typically require many bridges, but there is a lack of resources and skills to produce them.”

Ease of transport and construction in remote areas was a key consideration in the early design phase notes Hervé Blanc: “We developed a structure that does not require welding on site, and which can be assembled without heavy lifting devices. In some cases, the girders can be offloaded and pushed into place with an excavator, or sometimes by the truck that delivered them. It takes around five days to install a typical two-lane (nine-metre wide) bridge that is 40 metres in length.”

The only preparatory work that needs to be done is preparing the bridge’s abutments. That can be done by an onsite partner who can complete the work while the bridge is being manufactured and shipped.

Simple design makes transport simple and efficient

Matière adapted the design to ensure two of the box girders which form the basis of the Unibridge® could fit into a standard shipping container. “Our box girders are 11.4 metres in length, ensuring two can fit into each container,” says Hervé Blanc. “The girders can be pinned on site to create a maximum length of 60 metres. But if you include piles, you can extend the length of the bridge significantly. We’re currently constructing a Unibridge® in the Philippines which will be four kilometres long. There is no limit on the width of the Unibridge® as the box girders can be simply linked with spacers.”

Weight saving with S460M

Another consideration was keeping the weight of the container below 25 tonnes. “Thanks to the use of ArcelorMittal grades such as S460M, weight is not an issue,” says Hervé Blanc. “In the beginning we constructed the entire bridge from S355, and a typical box girder weighed 12 tonnes. Today we are using more S460M, and the average weight is 10 tonnes, a saving of almost 20 percent. Now we are looking at replacing the S355 with S460M from ArcelorMittal to achieve even greater weight savings. That will reduce the cost of transporting and installing the bridges.”

Low maintenance steels extend bridge life

One of the key advantages of ArcelorMittal’s steels is that they don’t need a lot of maintenance as Hervé Blanc explains: “ArcelorMittal’s steels are very tough! The bridge simply needs a fresh coat of paint every 15 to 20 years to protect it. In some areas we recommend a C5 paint system due to the marine environment.”

A sustainable solution thanks to steel

As the Unibridge® is prefabricated, there is no waste produced on site. All scrap steel produced in Matière’s factories is recycled or reused. The sustainability of the solution is further enhanced as it can be transported by ship from Matière’s plants in Europe.

The bridges themselves can be fully recycled at the end of their life or disassembled and reconstructed in another location. “The company which is building a traffic deviation around Strasbourg, France is renting two of our Unibridge® solutions to divert traffic around the roadworks,” says Hervé Blanc. “They will be in place for two years before they are dismantled and reassembled in another location.”

To date, Matière has installed over a thousand Unibridge® solutions in more than 35 countries around the world. “The introduction of the Unibridge® in 2004 was the beginning of Matière’s success story,” says Hervé Blanc. “But every Unibridge® is also a human success story. They can cut a journey that normally takes a day, to just an hour. This dramatically changes the way people in remote areas live and interact.”

About Matière

Matière was founded in 1932 and is still a family-run company. The business operates three plants in France and one in Belgium. All the plants produce components for Matière’s bridge business. In addition to the Unibridge®, Matière produce reinforced and prestressed concrete bridges, metal bridges, and composite structures which use both metal and concrete. The company is also involved in the repair of concrete and metallic bridges. Around 65 percent of its bridges are exported outside Europe.

For more information, visit: www.matiere-tp.com

About ArcelorMittal Projects

ArcelorMittal Projects has a global network of offices to support customers wherever their projects are located. We can leverage all parts of the ArcelorMittal group and source steel products from different segments.

We have specialty stocks of steel strategically located around the globe. That enables us to provide a complete and customised range of steel solutions and services, which include dedicated project management and prefabrication.

For more information, visit: https://projects.arcelormittal.com

Text: ArcelorMittal Europe Communications, Constructalia
Images: Matière

Related link(s)

Matière Unibridge® banner

A Matière locomotive Unibridge®

A Matière Unibridge® in Kourouba, Mali

Pont de Juba: a Matière Unibridge® in Freetown, Sierra Leone

Matière Unibridge® with piles

Matière Unibridge®

Matière logo

Matière

We have added more technical details for structural steel grades! Check out our newest steel grade pages that include mechanical and chemical property details.

S355 structural steel grades

S355 structural steel grades are mainly used in building and civil engineering applications.

These structural steel grades are carbon-manganese steels with guaranteed minimum mechanical properties (yield strength and tensile strength) and with satisfactory ductility. They offer good weldability with all conventional welding processes. In addition to their excellent mechanical properties, structural steels have satisfactory toughness values, especially with +N or +M.

S420 and S460 high strength structural steel grades

S420 and S460 high strength structural steel grades are weldable, fine grain structural steels that offer good weldability with all conventional welding processes.

These steels are used for welded parts that must withstand high levels of strain. Typical applications are bridges, long span structures, high-rise buildings, and other architectural structures.

Each grade can be obtained with guaranteed impact properties at -20°C (N or M grades), or for low-temperature applications, at -50°C (NL or ML grades).

Text: Constructalia, ArcelorMittal Europe - Long Products
Images: ArcelorMittal Europe - Long Products, Gdańskie Inwestycje Komunalne, OMA/Sebastian van Damme, Chuck Choi/Foster & Partners

Related link(s)

Truss with HISTAR® steel

H section in S 460 M used for the new Triangle bridge in Dunkirk

The relationship between steel and skyscrapers has been ongoing for over one hundred years, and this affiliation is growing ever stronger. In the 1930s, steel facilitated the boom of high-rise construction, while high strength steel ushered in its resurgence in the 1970s. Thanks to its affordability and durability, steel has always been the material of choice for the design and construction of tall buildings’ principal structural systems.

The current times bring with them a growing concern for sustainable development, including contradictory notions on the affordability, safety, and environmental impact of steel. This has resulted in some misperceptions about the role of steel in high-rise construction. In response to this, the Council on Tall Buildings and Urban Habitat (CTBUH) and ArcelorMittal partnered together on a research paper entitled ‘Steel and Skyscrapers: A Productive History and a Sustainable Future’ in order to illustrate the recent developments in the partnership between steel and skyscrapers that make it a strong, sustainable choice for high-rise construction.

Overview

This research paper delves into the sustainability of steel while examining its impact on the life cycle analysis of a building with an overall aim to broaden innovation in design via an analysis of new ideas for the creation of sustainable, cost-effective, and optimised buildings for the future.

This paper provides a summary of the latest innovations in specifications with a special focus on high strength steel that can result in a reduced amount of steel being required for a building’s construction. The paper presents design methods that can streamline fabrication and erection for a reduction of energy usage during construction in addition to evaluation ideologies, such as standardising floor area, that increase operational efficiency and reduce negative environmental impact.

Findings

“Sustainable development is not a fixed state of harmony, but rather a process of change in which the exploitation of resources, the direction of investments, the orientation of technological development, and institutional change are made consistent with future as well as present needs” (WCED 1987). As our global knowledge and understanding deepens, it is clear that we all must band together to discern innovative and sustainable methods that will allow for greater economic and social development with the minimisation of environmental damage taking its vital place at the core of these methodologies.

In the same way that tall buildings revolutionised the urban environment, steel has been, and will continue to be, revolutionary and transformational in terms of the correlation between tall buildings and sustainable development. It is the responsibility of those involved in the design and construction process to incorporate the advice of the experts, innovations, and highly sustainable building products in such a way that we will reduce our carbon footprint for future generations.

Text: Constructalia
Research paper: Shelley Finnigan (Global Technical Sales Engineer, Head of Technical Sales & Marketing, Americas, ArcelorMittal), Dario Trabucco (CTBUH Research Manager, Council on Tall Buildings and Urban Habitat), Jean-Claude Gerardy (Head of Export, Sections and Merchant Bars, ArcelorMittal), Nicoleta Popa (Head of Global R&D Construction Applications, Infrastructures and Long Products, ArcelorMittal)

Related link(s)

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ArcelorMittal Office Building: general view

Logo CTBUH

Kompleks biurowy Varso Place: widok z lotu ptaka

Steel and Skyscrapers: A Productive History and a Sustainable Future

The steel demand outlook is robust, and increasingly, supply will come from recycled scrap.

Steel’s contribution has made it a preferred tall building construction material for more than a century