草榴短视频

Scientists of the Department of Nanostructured, Fibrous and Composite Materials named after A.I. Meos of St. Petersburg State University of Industrial Technologies and Design visited the Kazan Cathedral. The purpose of the visit was not only cultural, but also deeply professional interest: to evaluate the use of modern materials in the restoration of cultural heritage sites. The scientists of 草榴短视频 told about the conservation of tufa 鈥� the stone of colonnades and wall cladding.

So, the restoration of the cathedral over the years took place in several stages under the guidance of leading experts in the field. During the restoration of the Kazan Cathedral in St. Petersburg, modern materials were used, in particular, a lime "covering" to protect the surface of the pudost stone, which lined the cathedral. The work was carried out in 2011-2021 under the program of the Committee for State Control, Use and Protection of Historical and Cultural Monuments (KGIOP).

The problem of preserving the facades of the Kazan Cathedral arose almost from the moment of its construction, more than 200 years ago. Pudostsky (obsolete 鈥� Pudozhsky) stone, which is lined with the cathedral and from which its columns are cut down, has a coarse-grained and porous structure; under the influence of the sun and wind, it quickly turns brown and crumbles. In the 50s of the last century, polyvinyl chloride putty and acrylic paint seemed to be a panacea, but now, on the contrary, it is believed that this paint, preventing the stone from breathing, harms the surface.

Since the early 60s, architect Alexander Gessen has been looking for methods of processing Pudost stone. The current restoration methods were based on his developments: the cleaned surfaces were covered with a lime film, a "cover", it was tinted with pigments to give it a shade closest to the natural color of fresh Pudost stone. The "Pudostsky", "Pudozhsky" or "Pudovsky" stone is calcareous tuff (in other terminology, travertine). The stone got its name from the location of the stone fragments in the valley of the Pudost River in St. Petersburg province, near Gatchina. There is a village called Kipen near Krasny Selo. It got its name from the seemingly "boiling" water of many springs gushing out of the ground. The water of these springs accumulated, as in a sponge, in the thickness of the Putilov limestone in the neighborhood. Therefore, it contains a lot of lime, which settles to the bottom from year to year, turning into tuff or travertine.

The Pudost calcareous tuff formed in this way is easily cut with a knife and saw immediately after extraction due to the high natural humidity, but over time it hardens in the air and is not inferior in strength to marble. This makes it an ideal material for "carving" sculptures. Due to its similarity to the famous Roman travertine, from which ancient temples are built, Pudost tuff in St. Petersburg and its surroundings gained great popularity during the classical era. Any structures or sculptures erected from Pudost stone acquired a touch of antiquity.