Edge East Side Berlin – Lighthouse project for use of sustainable concretes in Berlin’s highest office building
In the heart of the German capital a building is currently going up that in terms of sustainability is in a class all of is own. The Edge East Side Berlin skyscraper of 142 m height with an office space of 65, 000 m² will become a landmark in Berlin’s district of Mitte and the new headquarters of Amazon Deutschland. For the thousands of people who will work here in the future there will be many technological innovations at their workplaces. But the possibly most fundamental change will be hidden to the untrained eye: the building demonstrates that a new, radically clinker-efficient concrete can be used on a large scale. The cement used consists to only 28 % of clinker, to 34 % of powdered limestone and to 38 % of granulated blast-furnace slag. The resulting concrete was successfully used in the 32nd and 33rd floor. At only 130 kg CO2 per m³ the concrete used underbids an average standard C40/50 concrete by more than one half.
In addition to the challenging mix formula, the project was for all participants from Allianz Real Estate, Züblin, Edge, alcemy to Master Builders Solution, Zementwerk Berlin or Lowke and Schiessl the ultimate litmus test for actual application of radically clinker-efficient concretes on the construction site. The project demonstrates one thing clearly: powdered limestone functions in large quantities as a scalable substitute for clinker. Far beyond that what is currently propagated, for example by the Association of German Cement Works (VDZ).
The presentation illustrates how in coordinated agreement and close cooperation of all parties involved in the project and with the support of close-meshed quality control such sustainable concrete can be produced and successfully implemented.
