Accumulated Deformations of the Historical Development of St. Petersburg

Abstract

An analysis of the deformations of the ordinary historical buildings of St. Petersburg, accumulated over the past 150–200 years, is presented. An effective way to assess the accumulated unevenness of sediments and rolls of historical buildings is proposed, which makes it possible to obtain a reliable idea of the shape of the deformation of the building. On the example of a representative sample of buildings from two central parts of the city, it is shown which forms of deformations prevail in the historical center. It was revealed that in half of the cases deformations occur in the form of bending in the longitudinal direction and roll of the facade walls outward in the cross section, which is most dangerous for buildings. The dependences of the relative unevenness of the settlement of historical buildings on the ratios of their length and width to height are given. The reasons for the formation of a characteristic type of deformations in the form of a bend are noted. The results of the assessment of the accumulated relative unevenness of sediments that buildings received in the course of their existence made it possible to establish that the accumulated deformations are more than an order of magnitude higher than the maximum permissible values for similar structures of new construction. At the same time, the operational suitability of buildings is maintained, which indicates their durability under the condition of constant maintenance and regular repairs. It is proposed to take into account the accumulated unevenness of settlement when assessing the category of technical condition of historical buildings and monuments. On the basis of on the conducted research, proposals are made to clarify the requirements of the current norms regarding the appointment of maximum additional deformations of brick historical buildings and cultural heritage sites.