METHOD OF EVALUATION OF MECHANICAL PROPERTIES OF THIN-WALLED REINFORCED CONCRETE STRUCTURE UNDER ACTION OF STRETCHING AND COMPRESSION AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 1997 - IPC

FIELD: measurement technology. SUBSTANCE: sample in the form of hollow cylinder is simultaneously loaded both by compressing load on system of distributing beam supports from hydraulic jack and by stretching load by pumping air from source of pneumatic pressure into volume of closed elastic chamber which rests against concrete core and exerts uniform pressure on internal surface of hollow cylinder perpendicular to it. Loading is carried out by steps with holding at each step to measure present values of deformations of reinforcement and concrete, width of opening of cracks and distances between them. Device for implementation of method has base 1 which carries core 2 made fast to it. Sample 3 in the form of hollow cylinder is put on core with clearance to its external surface. Loading gear in the form of elastic closed toroidal chamber 4 to which space pressure source 5 is connected is placed in clearance between core 2 and sample 3. Gear is fitted with lever-hydraulic system manufactured in the form of distributing beam supports 7 interjoined by means of hinges, hydraulic jack 8 coupled via connecting hoses 9 to oil pump made fast to core 2 and base 1. Two ring spacers 10 made from material with low deformation modulus are positioned on proper butt of sample in the form of hollow cylinder. Ball bearings 11 are located between surfaces of two rigid distributing ring dies 12 facing each other and put on ring spacer 10 on side of free butt of hollow cylinder 3. Diameter of each die is equal to that of hollow cylinder 3. Lower belt of beam supports 6 of lever-hydraulic system is mounted on free surface of rigid distributing ring die. EFFECT: improved authenticity of method, increased functional efficiency of device. 2 cl, 2 dwg