Modernization of pulses automatic circulation method for determination of ultrasound speed in dependence of applied stress

New method for determination of stresses in metal constructions using modified procedure of ultrasound speed measurement is proposed. The method is significantly more accurate. New element, the pulse counter, is introduced into measuring setup. It makes possible to measure pulse with the maximum amplitude and to store it in the counter. Experimental data on the measurements of ultrasound speed in bridge constructions are presented. This method of ul-trasound speed measuring improves non-destructive control of materials and constructions. The method is based on the correlation between the ultrasound speed and materials properties such as structure, strength, yield strength, impact stress, etc. Nature and quantitative parame-ters of the above correlation were studied in laboratory tests. Relative variation of ultrasound speed is usually 0,1...1% and it can be measured by special equipment. Great potential of this method were confirmed in laboratory and in situ.