Stand-alone NDT system for tensile force estimation in cables and tie rods

Non-destructive techniques represent a very relevant tool in many engineering fields and play a relevant role in the case of preservation of cultural heritage and historical structures. This is particularly true in those countries exposed to seismic risk and other relevant natural hazards. Health conditions of masonry constructions often depend on the interaction between curved structures, such as arches and vaults, and tie-rods installed to neutralize the related horizontal forces. In the present paper, key aspects related to the development of a stand-alone vibration-based monitoring system for tensile load estimation and monitoring in cables and tie-rods are presented in the light of the available technical literature. Sample experimental results obtained after the installation of the monitoring system on one of the cables of a sample arch steel roof are finally illustrated.