K U Leuven, Department of Civil Engineering
Since 1995, several PhD researchers at the Civil Engineering Department of K.U.Leuven, have been developing the use of geo-electrical measurements of electrical conductivity as a non-destructive technique for masonry. With a series of electrodes, the distribution of the electric conductivity over a surface and into the depth of the masonry, gives 3D information on masonry layout, homogeneity and quality. Nowadays, the technique has evolved into a mature state and is regularly used in conservation practice, e.g.: the Castle of Beersel (B), the quay-wall of ‘s Hertogenbosch (Nl), the windmill at Pendrecht (Nl), the Church of Our Lady, Brugge (B), the bell tower of the church at Hoogstraten (B). From these case studies, an appraisal of the practical applicability of this technique in the actual assessment of masonry walls is undertaken. The main questions that arise are the influencing factors of humidity and salts, how to quantify the data and assess the applicability of it to the quality control of grout injection.
geo-electrical measurements, non-destructive technique, electric conductivity, homogeneity