TY JOUR TI GRAVITATIONAL CONCRETE MIXERS WITH UNIFIED DRIVE MECHANISMS KW gravitational concrete mixer KW unification KW drive mechanism KW working body KW planetary gear KW specialization KW cooperation JO Bulletin of Belgorod State Technological University named after. V. G. Shukhov AU Kaytukov, B.A. AU Skel', V.I. AU Goryaynova, P.O. PY 2019 IS 4 PB Belgorod State Technological University named after V.G. Shukhov