Prestressed natural stone elements

Our building material has inherently excellent characteristics that are not only technically proven but have also shown their worth in historic buildings over centuries. In addition to its weathering resistance, our natural stones also feature high compressive strength, exceeding by far the values achieved e.g. with concrete.

While concrete gets his bending tensile strength by embedding steel reinforcement bars, natural stone gains it by using steel tie rods. Boreholes or recesses are drilled into the tensile zone of the natural stone and tendons (usually made of stainless steel) are inserted. These are then prestressed with a force defined in structural calculations. This gives the natural stone an excellent bending tensile strength, which allows a much thinner design as usually possible with concrete.

The applications are manifold, since this technique can be used for structural elements consisting of one or several pieces. The elements can be prestressed in our plant or directly on the construction site.

Current examples include:

• Architraves for the Colonnades on the Museumsinsel (museum island) in Berlin
• Architraves for the Museum Barberini
• Architraves and built-up lintels for the Schloss Berlin (Berlin Palace)