High steel prices opt for economical hollow-core


High steel prices opt for economical hollow-core

Scrap steel is at a shortage and the price of constructional steel has risen by 30 percent since February. To find out more about the causes of this effect, Concrete Issues met with Mr. Seppo Rajamäki, Vice President and Technical Director at Consolis, Europe's largest producer of precast concrete products and a consumer of 75 000 tons of steel yearly.

How is the high steel price affecting precast production?

On a short term the rapidly risen steel prices are somewhat tricky, as we have annual contracts that were made when prices where lower. In the long run, however, the high price of steel improves our competitiveness, as precast concrete requires significantly less steel than cast-in-situ methods or steel construction.

What precast/prestressed technologies are especially economical in today's situation?

The hollow-core (flooring) technology is the most economical system today. It enables longer spans, which in turn saves in foundation costs. Furthermore, hollow-core requires 40 percent less concrete and 50 percent less steel compared to a plain reinforced slab cast in-situ. The steel needed in hollow-core slabs is actually as little as 3.5 kg/m2!

Are there any changes to the production technologies in sight?

The final product is invariably the same and the production methods and investments must always be considered and compared to potential savings. I do not think there are any considerable changes in sight. We have optimized all our solutions in good time and this is now bearing fruit. From the beginning, our basic idea has been to minimize the use of raw materials and keep quality on a good level.

Can steel be replaced with self-compacting or fiber-reinforced concrete, for example?

An alternative to steel could be found in the mixing of, for example, plastic fibers into the concrete. This could possibly replace steel in the production of columns and beams, but it is a rather expensive solution and so does not necessarily make for savings in production costs. As for self-compacting- concrete, it is just another type of concrete and does not lessen the need for steel reinforcement, even though it is much stronger than the ordinary kind.

Looking to the future, where is Consolis heading?

Consolis has grown strongly and has financed this development entirely without outside funding. At present we are viewing the new EU countries with great interest, as they make for an exciting future prospect. On a general level, we intend to remain a supplier of construction materials. This means that we focus on production, delivery, and installation. Our role in a construction project is basically to set up the building frame. In the mean time, our technology division is constantly working at developing new products and innovations. The Consolis Housing Concept, for example, is a new method for fully prefabricated construction, with no visible joints! The possibilities with precast concrete are virtually endless, and this makes us look to the future with confidence.