Messung der Druckspannungen an Mauerwerk über die Schallgeschwindigkeit in den Mörtelfugen/ Measurement of compressive stresses in masonry making use of the sound velocity across mortar joints

The paper presents an in-situ method which is suited to measure compressive stresses in masonry with joint thickness < 10 mm. It is shown on two masonry specimens made of brick and mortar according to historic mixes (Church San Vitale, Ravenna, Italy) how the sound propagation velocity increases with increasing compressive stress. In case of this mortar, compressive stress can be determined in