ArcelorMittal continues to leap forward in steel solutions with the release of Steligence®. Ushering in a new wave of high-performance building and construction techniques, this fresh and innovative concept ensures that each steel component interacts in a complementary way.

"Taking a holistic approach to sustainable construction." (Prof. Olivier Vassart)

Steligence® was developed after a number of years of scientific and industry reviewed research that has resulted in a profound new approach to construction built on a strong foundation of sustainability.

Addressing current issues in the building industry, Steligence® is a philosophy that incorporates all elements of design and encourages more communication among the architectural and engineering experts involved in a building project.

Keeping only the strongest elements of traditional construction methods, Steligence® incorporates the best available technology in steelmaking and a new and fresh approach to sustainability in terms of the overall design process and the future life of a building.

The Steligence® approach includes a broad range of steel products for construction which individually add value, but together represent a compelling portfolio with a range of defined benefits.

A win-win solution

During a speech at the London launch event, Greg Ludkovsky, ArcelorMittal’s global head of research and development, explained that “as climate, energy and resource scarcity intensifies, win-win solutions like Steligence® become imperative for business and society at large. Buildings play a huge part in all our lives, so creating a construction concept that improves their social, economic and environmental impact while dramatically enhancing their functionality and aesthetics has been a huge but important challenge.”

The site of the Hotel Martin's Patershof – the result of renovating and transforming a church into a four star hotel – was the first to implement an innovative solution combining composite flooring / lightweight concrete, namely Cofraplus 77 LS, with Argex concrete consisting of expanded clay aggregates. This project was the culmination of nearly two years of research and development by ArcelorMittal Research Center and the close attention paid by the engineers to Arval’s prescription to meet the needs of the builder-promoter.

The aim of the Martin’s Patershof project was unique: to create, within the heart of a nineteenth century church in Mechelen, a five-storeyed hotel with 77 rooms in a single framework. The renovation and transformation of the site has also been the first to apply composite flooring with lightweight concrete. 

Composite flooring

Composite Floor Slab is a mixed construction system consisting of a steel sheet which serves as shuttering for concrete and reinforces the slab, totally or partially replacing the tensile reinforcements.

It is essential to achieve a bond between the steel and concrete that is stronger than the horizontal stresses to which the slab is exposed.

In this system, the concrete-steel bonding is achieved thanks to the special design of the steel sheets. These sheets are embossed with frustum-shaped projections, repeated indefinitely, both on their horizontal surfaces and on the sloping sides.

During assamblence and the concrete grouting, the self supporting steel deck constitutes a working platform.

A new solution for renovation

In new constructions, light flooring is particularly useful in multi-storeyed buildings because it significantly reduces the dead weight and lightens the structure and the foundations. But this product has also proved to be useful in renovation works where it is advisable not to overload the existing masonry beyond its limited bearing capacity. In addition, it enables increase in span length without forestay during the concrete grouting.

A solution suited for the Martin’s Patershof hotel project

ArcelorMittal’s decision to use Arval’s composite floor Cofraplus 77 LS combined with Argex concrete is justified for several reasons. First, the configuration of the site required the manual transfer of all the materials through the entrance gate which was only 1.40 m wide.

Then, the thickness of the slab had to be 23 cm, taking the permissible dead weight by adding lightweight concrete up to 1.5 kN / m², which amounted to 450 tonnes for a floor space of 3000 m². The last reasoning was considered decisive by the contractor as the land on which the church is based does not allow the use of conventional composite floors.

The ultimate load bearing capacity was weak. Furthermore, the contractor wanted to avoid the use of concrete props in the middle of this dense structure with 5 floors.

Despite its well-known rigidity within the range of composite floors, Cofraplus 77 did not have the permit to cross the limit of 3.20 m with 23 cm of normal concrete. The Argex concrete had the permit to do so. The project technicians used structural concrete with density ranging between 16 and 18 kN/m3 instead of 25 kN/m3. Hence, for a 15 cm thick slab, there was a reduction of about 1 kN / m².

An innovation that met all the objectives: stability and fire resistance for engineers, approved planning and financing savings for the developer-contractor.

Photos: © Arval by ArcelorMittal