CONTROL OF A REAL SIZE CONCRETE STRUCTURE PARANALYSIS OF ULTRASONIC CODA WITH BIAS COMPENSATION

Abstract

he analysis of ultrasonic coda (CWI) is considered apromising method for non-destructive testing and evalua-tion of complex material such as concrete, for its abilityto evaluate elastic properties of material with an extremeaccuracy. In order to further improve the reliability of themethod, we have designed an experimental protocol forcompensating biases from variations of the ambient tem-perature which frequently affect ultrasonic measure-ments. This protocol allows compensating various biases(thermo or thermo mechanical) stemmed from variationin ambient temperature without extensive knowledge oftheir mechanism. Furthermore it can be applied withoutdemanding a reference specimen. A test was carried outon a real-size concrete structure for monitoring locallytensile stresses and cracks, which indicates that in situquantitative monitoring of real concrete structures is pos-sible with CWI.