The use of ultrasound for determination of thickness of the glass panes of windows

Abstract

TIt was shown that when investigating the glazing units of windows by ultrasound it is necessary to determine the thickness of the glass panes. For that purpose the possibilities of one side ultrasonic measuring methods, when the longitudinal and shear waves are excited in the glass pane, are analysed. New algorithms for calculation of propagation velocity of the shear waves and the thickness of the glass pane are developed. The algorithms are valid when the incidence angle of acoustical signals to the glass surface is known, but the sound velocity in the glass media is unknown. For the measurement of the shear wave velocity and the thickness of the glass pane it is proposed to use the multiply reflections of acoustical signals propagating between the different points of the glass surface. It enables to eliminate the influence of propagation time of ultrasound signals in the prisms of angular ultrasonic transducers and the accuracy of measurements is increased. The results of experimental investigation are presented.