Practical restoration-related experience with creation of basement level and underground parking into and near architectural monuments in down-town of Saint-Petersburg

Geotechnical construction in Saint-Petersburg is governed by the specific features of geological conditions. There is large thickness of soft water saturated soil underlays at the basement monuments and historical buildings. This soft water saturated soil become thixotropic under insignificant dynamic effect (construction action, transport, seasonal freezing and etc). The experience of the renovation, reconstruction old buildings with construction of the deep basements, underground parking in the inner yards or near the architectural monuments in the central part of Saint- Petersburg are given in this article. This paper provides the description of geotechnical solutions, which were realized on the various cultural heritage buildings, such as Catholic Church of St.Catherine on the Nevsky prospect, Taurid Palace, Christmas Church on the Sands, shopping mall «Galeria» on the Ligovsky prospect. The authors analyzed some failures of buildings and facilities as the result of incorrect methods and technologies of the deep excavation.