COMPARATIVE APPLICATION OF THE MICRO-SEISMIC TECHNIQUE AND THE IMPACT-ECHO TECHNIQUE TO THE AUSCULTATION OF CONCRETE SLABS

Abstract

This study concerns auscultation of concrete slabs on theplanes parking of le Bourget airport in the frame of col-laboration with Aéroports de Paris company (ADP).Constructed since several decades, concrete propertiesand slabs thickness were unknown and one of the slabspresented important cracking. For auscultation, micro-seismic technique and impact-echo technique wereemployed together and comparatively. Results show thatmicro-seismic technique determines slabs thickness withaccuracy of centimeter without any hypothesis on acousticproperties of concrete, necessary in the case of impact-echo technique. Moreover, micro-seismic technique char-acterizes concrete’s quality on the base of Yang modulusand distinguishes well superficial and deep cracking, giv-ing by this way more consistent information then impact-echo technique on mechanical integrity of tested element.In return the simplicity and swiftness of impact-echo andcan be exploited judiciously for assessing local variationof geometrical and mechanical characteristics of slabs.