The Kaiser Wilhelm National Monument on the Kyffhäuser, or Kyffhäuser Monument or Barbarossa Monument for short, was erected in honour of Kaiser Wilhelm I. The 81-metre-high monument thus joins the ranks of ostentatious 19th-century monuments such as the Monument to the Battle of the Nations in Leipzig and the Kaiser Wilhelm Monument at Porta Westfalica. Inside the castle complex, Barbarossa is enthroned, the sandstone carved figure of Frederick I, who seems to have just awakened.
The location, the permanent moisture penetration in the area of the natural stone masonry and the lack of care and maintenance of this type of object had led to considerable damage in the area of the jointing and the sandstone. A necessary consequence of the low maintenance was a general renovation of the monument from 1994 to 2014. In order to increase the durability, especially of the joints, as well as the flank adhesion, among other things, examinations were carried out by the MFPA Weimar together with the restorer Romstedt. The result of these investigations was the mortar maxit mur Kyffhäuser with a grain size of 0 - 2 mm and a liquid dispersion that was added.
For grouting the natural stone in the different areas of the monument - retaining wall, castle complex, Barbarossa tower and parts of the terraces - a formula mortar was developed that exactly matched the natural stone and the specific requirements maxit renovation of this object. With this individual mortar, maxit mur Kyffhäuser, the surfaces were grouted by hand. In addition to a reliable mortar formulation, craftsmanship was therefore required above all! The aim was to achieve a uniform appearance in terms of structure and colour across the large number of individual sections in the monument.
Another decisive factor for the successful joint renovation of the 120-year-old monument was and is a reliable adhesion between the mortar and the natural stone. This was ensured by means of a specially developed acrylate dispersion (WBC), which was added in small quantities.
For the installation of the sandstone slabs on the terraces, maxit coll MKT Mittelbettkleber Trass, recipe Kyffhäuser, was used for levelling and embedding the slabs.