TY JOUR TI ANALISYS OF PERLITE ADDITIVE AS INTERNAL CURE AGENT IN CEMENT CONCRETE SYSTEM KW hardened cement paste KW lightweight aggregate KW perlite KW internal cure KW shrinkage JO Bulletin of Belgorod State Technological University named after. V. G. Shukhov AU Sidorova, A.S. PY 2024 IS 9 PB Belgorod State Technological University named after V.G. Shukhov