Monitoring and Evaluation of Sandstone Decay Adopting Non-Destructive Techniques: On-Site Application on Building Stones

Abstract

This paper focuses on the characterization approach to evaluate the decay state of Pietra Serena of historic buildings in Florence (Italy). Pietra Serena is a Florentine sandstone largely used in the city especially during the Renaissance; it is a symbol of cultural heritage of Florence and constitutes a large part of the city center, which was named a World Heritage Site by UNESCO in 1982. Unfortunately, many environmental factors negatively affect the stone, increasing damage and the danger of falling material. Any detachment of stone fragments, in addition to constitute a loss in cultural heritage, can be dangerous for citizens and the many tourists that visit the city. The use of non-destructive techniques (NDTs) as ultrasonic and Schmidt hammer tests can quantitatively define some mechanical properties and help to monitor the decay degree of building stone. In this study, the NDTs were combined with mineralogical, petrographical, chemical and physical analyses to investigate the stone materials, in order to correlate their features with the characteristics of the different artefacts in Pietra Serena. Correlations between the NDTs results and the compositional characteristics of the on-site stone were carried out; such discussion allows to identify zones of weakness and dangerous unstable elements.

La Piedra fundacional de la iglesia de San Blas (Cuenca, Ecuador). Diagnóstico interdisciplinar y orientaciones de conservación

“…Desde su génesis, diferentes pueblos han utilizado los materiales que la naturaleza ofrece por sus características físicas y abundancia, los cuales han contribuido al desarrollo de diferentes tipos de asentamientos y tipos arquitectónicos (Lambourn 2006;Zeren & Karaman 2015;Muiños Barros 2019), y con el tiempo, se han constituido en parte de la historia (Naoom & Mohammad 2022) e identidad, es decir, el uso, conservación y evolución de los materiales denota su trascendencia (Aguirre Ullauri 2021), al punto de que se puede representar la historia de la arquitectura a través de la historia de los materiales (Yahya & Abdul Saamad 2014). Entre ellos, la piedra como material duradero, ha sido ampliamente utilizada, pero también es propensa a diferentes tipos de deterioro según las condiciones climáticas, propiedades petrofísicas (Salvatici et al 2020), formas de uso, e incluso intervenciones.…”

Close-Range Sensing and Data Fusion for Built Heritage Inspection and Monitoring—A Review

“…The full 3D sonic or ultrasonic tomographies are especially devoted to the internal study of pillars and columns [234]. Many examples of built heritage inspection through sonic and ultrasonic sensing can be found in recent bibliography [207,229,[235][236][237][238][239][240][241][242][243].…”

A Multidisciplinary Methodology for Technological Knowledge, Characterization and Diagnostics: Sandstone Facades in Florentine Architectural Heritage

“…The diagnostic project involved first the historic analysis and architectural survey, the latter carried out with a 3D laser-scanner and digital photogrammetry, then the investigation on site through an ultrasonic pulse velocity test and a Schmidt hammer test-both nondestructive techniques (NDT)-were performed [7,8]. In addition to the NDT tests, a few destructive tests (DT), with the aim of validating the NDT results through the petrographic and mineralogical features of the investigated rocks, were carried out.…”