Defining a Non-Destructive In Situ Approach for the Determination of Historical Mortar Strength Using the Equotip Hardness Tester
Source abstract
Abstract
The determination of mechanical parameters of historical mortars is a crucial aspect in the analysis of masonry in ancient buildings, especially for evaluating their quality and planning the appropriate restoration interventions. Due to conservation reasons, creating a comprehensive database is generally not possible because cutting out masonry specimens relates to damaging historical structures. This study starts with the need to characterize the mortar quality of different buildings in the town of Camerino (Central Italy) which has been strongly damaged by the 2016–2017 seismic sequence. A non-destructive collecting data strategy based on the use of the Equotip hardness tester (EQ) has been set up by evaluating the most appropriates impact strategy (single or repeated) and the range of measurements to calculate the basic statistics. The seismic damage suffered by the buildings allowed the rare opportunity to take samples from several walls and carry out laboratory tests to determine their Uniaxial Compressive Strength (UCS). The comparison between the results of the two types of tests made it possible to calibrate a relationship between the EQ values and the UCS. The Pearson’s coefficient of determination derived from an exponential interpolation (R2 = 0.81) confirmed a strong relationship between the EQ values derived from the tests on the specimens and the UCS. Moreover, comparing the in situ EQ measurements with the ones performed on the specimens prepared for the compressive tests, a general underestimation of the in situ EQ values has been observed, possibly due to the presence of a superficial alteration layer of the exposed mortar. From these results, we propose a correction of the in situ measurements able to obtain a more appropriate strength estimate of the historical mortars.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Building materials and conservation · Geophysical Methods and Applications · Masonry and Concrete Structural Analysis
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Affiliations
Scuola di Scienze e Tecnologie, Sezione di Geologia, Università di Camerino, Via Gentile III da Varano, 62032 Camerino, Italy
Dipartimento di Fisica e Geologia, Università di Perugia, Via Faina 4, 06123 Perugia, Italy
Dipartimento di Scienze, Ingegneria della Materia dell’Ambiente ed Urbanistica (SIMAU), Università Politecnica delle Marche, via Brecce Bianche 12, 60131 Ancona, Italy
GeoMORE S.r.l., Via Gentile III da Varano, 62032 Camerino, Italy
Scuola di Scienze e Tecnologie, Sezione di Chimica, Università di Camerino, via S. Agostino 1, 62032 Camerino, Italy
Funding
Horizon 2020
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Show source-provided references
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