FIELD: construction engineering; examination and tests of concrete constructions in the course of operation. SUBSTANCE: prior to drawing a sample by means of drilling tool, section of concrete under test is wetted and surface strength of concrete is determined taking into account its moisture content; then, drilling unit is mounted where required and is placed in operation at constant load; in drawing a sample, power required for drilling, as well as amount and race of motion are measured; the results of measurements are processed in computer through comparison of the data obtained with the specified magnitudes. Data are presented in form of graphs of power, motion and rate of motion of drilling tools characterizing layer-by-layer strength of concrete on computer monitor accompanied by display of digital data for each graph. EFFECT: enhanced accuracy of analysis. 4 dwg
