Измерение акустических характеристик компактных бетонных строительных конструкций с помощью импакт-эхометода

Abstract

The impact-echo method is a resonant technique, which is based on using a short duration mechanical impact to generate stress waves and a transducer to monitor the surface displacement due to the arrival of direct and reflected stress waves. The impact-echo method controls concrete building structures, which the measured thickness H is at least six times smaller than other dimensions, and does not control compact samples, which the thickness H is comparable to other dimensions. The problem of compact objects control is that on the spectrum of a compact sample it is impossible to clearly determine the resonance frequency f0 ~ 1/Н against the background of numerous closely spaced frequency peaks. Another reason is that due to the strong influence of the geometric factor in compact samples, a geometric correction factor β is require to calculated for each new compact object. The article proposes a solution of these problems by using the multiplicative impact-echo method and various variants of the correlation impact-echo method.