TY JOUR TI TO THE QUESTION OF CONCRETE QUALITY CONTROL KW concrete KW control rules KW number of samples KW probability KW strength KW standard deviation KW reproducibility JO Bulletin of Belgorod State Technological University named after. V. G. Shukhov AU Loganina, V.I. AU Zaitseva, M.V. PY 2021 IS 6 PB Belgorod State Technological University named after V.G. Shukhov