METHOD TO TEST REINFORCED CONCRETE ELEMENT WITH LONGITUDINAL STATIC COMPRESSION AND DYNAMIC BENDING MOMENT Russian patent published in 2012 - IPC G01N3/20 G01M7/08 

FIELD: construction.

SUBSTANCE: using a resonance method, the lower internal frequency of reinforced concrete element oscillations is identified. A damaging single dynamic action is carried out at a tested reinforced concrete element. Higher harmonics of internal oscillations are filtered as they arise and comply with harmonics at the moment of the reinforced concrete element damage, from the lower harmonics, the frequency of which corresponds to the lower internal frequency of reinforced concrete element oscillations, and using the produced data, the actual values of dynamic parameters are estimated. Previously two or a series of identical reinforced concrete elements are manufactured. The resonant method is used to use to determine a lower internal frequency of oscillations of one of these elements taken as a reference, besides, it is exposed to a step-by-step static longitudinal compression, increasing the value of the static longitudinal force with each subsequent pitch in the range from zero to maximum permissible value. After each step of the longitudinal static compression, using the resonant method, the lower internal frequency of reinforced concrete element oscillations is determined, afterwards the curve is built on dependence between the internal frequency of oscillations and relative longitudinal static compression force, which is determined using the formula. The other tested reinforced concrete element is exposed to longitudinal static compression by a specified value and a damaging single dynamic impact with the specified value of the bending moment. The relative value of longitudinal static compression force is determined at the moment of damaging and using a curve of dependence between the internal frequency of oscillations and the relative value of the longitudinal static compression force, produced for a reference element, the lower internal frequency of oscillations is determined for this tested reinforced concrete element at the moment of damaging, which is taken into account when filtering higher harmonics of internal oscillations.

EFFECT: higher accuracy to determine an internal frequency of reinforced concrete elements.

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