Author(s)

A. Carpinteri & G. Lacidogna

Abstract

This study concerns the structural stability of three medieval towers, \“Torre Sineo”, \“Torre Astesiano” and \“Torre Bonino”, rising in the centre of Alba, a characteristic town in Piedmont (Italy). The geometrical and structural aspects of the towers were analysed and non-destructive tests were performed to assess the evolution of damage phenomena. The damage processes underway in some portions of the masonry were monitored using the Acoustic Emission (AE) technique. This method makes it possible to estimate the amount of energy released during the fracture process and to obtain information on the criticality of ongoing processes. Finally, an ad hoc theory based on fractal concepts for assessing the stability of masonry structures from the data obtained with the AE technique is proposed. Keywords: acoustic emission monitoring, brick masonry, crack propagation, damage assessment, fractal analysis, in situ tests, non-destructive tests, structural stability. 1 Introduction Non-destructive and instrumental investigation methods are currently employed to measure and check the evolution of adverse structural phenomena, such as damage and cracking, and to predict their subsequent developments [1,2]. This study addresses some of the afore-mentioned problems deemed of special significance. Towers geometry was determined through the customary survey methods. Damage, cracking and the evolution of these phenomena over time were assessed through non-destructive techniques: tests with flats-jacks were conducted in

Keywords

acoustic emission monitoring, brick masonry, crack propagation, damage assessment, fractal analysis, in situ tests, non-destructive tests, structural stability.