Physical and mechanical characterization of vernacular dry stone heritage materials: Schist and granite from Northwest Portugal

Abstract

Knowing and understanding historical building materials and techniques is a fundamental step to ensure successful heritage preservation procedures. An experimental campaign was designed and implemented to acquire scientific information about the physical and mechanical behaviour of schists and granites used in Northwest Portuguese vernacular dry stone masonry. Results show schists strong anisotropy, and influence of foliation regularity, over the main physical and mechanical parameters. Granites isotropy and compact and heterogeneous fabric result in higher strength and lower water absorptions. Moreover, results show the negative effects of water over stones strength and elastic parameters.