The proper filling confirmation of the cavities in massive concrete structures of nuclear power plants by impact-echo method

Abstract

Nuclear power plants (NPP) are duty to certify their security for renewal of operating license. Security can be significantly affected by defects of ageing concrete reinforced structures. The methods, how to do in-service inspections of these aging structures of NPP more quickly, cheaply and reliably, are still being looking for. Advanced Impact-Echo method seams to be very hopeful. This paper is a part of extensive project and continues a number of papers published in Czech as well as in foreign. It brings a method description and a main results survey of the numerical modeling of the detection of grouted (repaired) voids in massive concrete structures. Cavities are filled by grouting polyurethan compound CarboPur WF. We try to find out if it is possible or impossible to confirm simply, by Impact-Echo method, if cavities have been filled properly. Consequently, these numerical predictions will be verified on real (scaled 1:1) specimens in NRI Řež as a part of this project as well.