Engineering geological properties of loess in the town of Silistra

Loess sediments build 70% of the soil base of the town of Silistra. They represent good ground base for construction at natural water content but their technogenic moistening provokes collapse or subsidence of buildings and facilities. About 30 buildings are affected by similar deformations. Within the range of the town loess sediments cover the old abrasion level (CAH), the floodplain terrace of the Danube River (T-0) and the slope between them (C). The paper considers the engineering geological properties of the loess deposits by distinguishing sections with collapsibility of the II type (total subsidence under geological load exceeding 5 cm), the I type (total subsidence of 0-5 cm) and non-collapsible sections. The sections are represented in a map of loess collapsibility, each of them is characterized with generalized lithological column and averaged physico-mechanical parameters. Additional geological information is presented in a geological profile crossing the territory of the town from the highest point to the Danube River.