Abstract

The paper describes in detail the application of a vibration-based structural health monitoring system installed in the “San Pedro Apostol” church of Andahuaylillas located in Cusco (Peru), a 16th century adobe church considered a representative example of South America baroque architecture. The results of three years of long-term vibration and temperature and humidity monitoring program are reported in detail in the paper, with a focus on the long-term and short-term correlations between natural frequencies and environmental parameters. The results demonstrate that an accurate estimation of the first eight frequencies in the range 2-6 Hz is possible in the case of complex adobe structure and the existence of an annual cyclical behavior of the natural frequencies with a clear correspondence with the changes in environmental conditions due to seasonal influences. The performed correlations of ambient conditions and structural parameters confirmed the presence of different timescales and their not negligible influence in the case of a vibration-based structural health monitoring assessment of adobe systems with large thermal inertia large thermal inertia.

Abstract

The current study aims to assist the preservation of the structural integrity of historical complex sites, utilizing smart instrumental monitoring / remote sensing. The main idea is that smart instrumental monitoring can provide important real-time information (records) of both the actual natural hazard(s) and the corresponding vulnerability, in terms of structural response and distress of structures and monuments of historically complex sites. The study focuses on the Acropolis Circuit Wall, where strain recordings via Smart Rod optical fibre sensors have been made possible. More specifically, wavelength recordings have been obtained and then converted into strain recordings, while the temperature influence has been taken into consideration. Furthermore, reference measurements have been defined during the initial system operation and then they are used for deduction of subsequent recordings. Strains recorded 2 and 1/2years after the initial system installation are shown, after the deduction of the reference measurements. Finally, strain variation between sensors located at the inner and outer side of the same optical fibre Smart Rod are shown.

Abstract

Soil movement may be induced by a wide variety of natural and anthropogenic causes, which are detectable in the local scale, but may influence the movement of the soil over vast geographical expanses. Space borne interferometric synthetic aperture radar (InSAR) measurements of ground movement provide a method for the remote sensing of soil settlement and uplift over wide geographic areas. Based on this settlement and uplift evaluation, the assessment of the potential damage to architectural heritage structures is possible. In this paper an interdisciplinary monitoring and analysis method is presented that processes satellite, cadastral, patrimonial and building geometry data, used for the calculation of settlement and uplift damage to architectural heritage structures in Belgium. It uses processed InSAR data for the determination of the soil movement profile around each case study, of which the typology is determined from patrimonial information databases and the geometry is calculated from digital elevation models. The impact on the historic structures is calculated from the determined soil movement profile based on various soilstructure interaction models for buildings. The resulting damage is presented in terms of a numerical index illustrating its severity according to different criteria. In this way the potential soil movement damage is quantified in a large number of buildings in an easily interpretable and user-friendly fashion. The processing of InSAR data collected over the previous 3 decades allows the determination of the progress of settlement- and uplift-induced damage in this time period. With the integration of newly acquired and more accurate data, the methodology will continue to produce results in the coming years, both for the evaluation of soil settlement and uplift in Belgium as for introducing related damage risk data for existing architectural heritage buildings. Results of the analysis chain are presented in terms of potential current damage for selected areas and buildings.