Concrete showing two faces

Figure: R. Mehl

All façade sections of the Zölly high-rise could be reached through mobile outer platforms

Figure: R. Mehl

The appropriate concrete composition was determined in the laboratory for construction chemicals of Nägelebau

Figure: R. Mehl

The optimum concrete specifications for manufacturing the precast elements are directly implemented in the factory‘s own mixing plant

Figure: R. Mehl

Owing to the high compaction energy of the vibrating table, the viscosity of the concrete must not be too high

Figure: R. Mehl

In the front, the so-called canopy structure being realized by means of sandblasting here. Etching gives it an even more sculptural appearance

Figure: R. Mehl

The elements ready for transport remarkably reveal the contrast between the individual parts of the surface

Figure: R. Mehl

Precast concrete elements made of a sophisticated concrete mixture were used up in building of the so-called „Zölly“ high-rise in Zurich. The addition of chemical additives enabled the application of an as low-slump as possible and thus lean concrete for the production of the high-quality components.

„The days are over when we just chose a concrete mixture from our list of formulations for a project!“ Dr.-Ing. José Colan waves aside. „On the contrary, every project brings about completely new challenges concerning the composition. For the Zölly high-rise, the architects requested for aggregates composed of marble as well as a bright sand. An Italian supplier could be found to deliver this material mix - the company Ferrari located in Grezzana near Verona,“ comments the plant manager at Nägelebau GmbH, a manufacturer of precast concrete elements based in the Austrian municipality of Röthis....