The Estimation of Compressive Stress Level in Brick Masonry Using the Flat-jack Method

The paper presents the methodology of in-situ testing based on the flat-jack device. The flat-jack method belongs to the minor-destructive tests (MDT). Beside NDT, MDT are recommended for historical buildings. In the paper the results of authors' laboratory studies on brick walls were presented. Tests were carried out using various types of flat-jacks in terms of their shapes and materials from which they were made. Additionally, during flat-jack tests various methods of displacement measuring including optical measurements based on a digital image correlation method (DIC) were performed. The studies allowed the authors to provide recommendations on the selection of the flat-jack type for determining compressive stress in brick masonry.