Cutting the grounds in the array of soil in the presence of caves and voids under it, washed with groundwater in gypsum, chalk and similar deposits, as well as abandoned quarries, coal developments, etc. p. In the presence of such voids and cracks in the pear massif, an additional load from the constructed structure can violate its balance, even if such soil possessed a sufficient bearing capacity. As a result, failures and precipitation of structures built on such soils are observed. They were so numerous during the construction of Kazan-Yekaterinburg (Sverdlovsk) railway line that a special survey of construction sites with karst formations was carried out.
