METHOD OF DETERMINING CRITICAL STRESS INTENSITY FACTOR OF CONCRETE Russian patent published in 2017 - IPC G01N3/24 

FIELD: construction.

SUBSTANCE: in the sample-prism of concrete a stress concentration area is created by means of applying two symmetrical incisions on one face of the concrete sample, after which the sample is loaded to destruction, the destructive load is measured and the critical stress intensity factor is determined by the formula where P is the destructive load, MH; Y - the correction factor; t - the sample width, m; H - the distance from the incision to the sample face, m; l - incision depth l=b/4, here b is the sample height, m.

EFFECT: increasing the accuracy and reliability of determining the critical stress intensity factor by forming areas of stress concentrations in the form of incisions.

1 dwg, 2 tbl