TY JOUR TI Unique Underground Construction KW underground construction KW structures KW waterproofing KW operation KW thermal insulation KW stability KW environmental properties KW reinforced concrete KW sandwich panel KW aggressive environment KW sanitary standards JO Journal of Technical Research AU Boytemirova, I.N. AU Kurzova, D.V. AU Sakalo, I.V. PY 2019 IS 5 PB INFRA-M Academic Publishing LLC.