Acoustic emissions - Insights into the decay mechanisms of thermally treated marbles

  • Since ancient times, marble has been the preferred material for monuments, sculptures, Ornaments and architecture. Though the stone is often a Chosen material, long-term exposure of marble results in cumulative deterioration of the rock fabric. The rate and extent of deterioration depends on the rock fabric and the climatic conditions. Besides the thermal vulnerability of marble, a combination of thermal and hygric fluctuation accelerates the deterioration process. The weathering sensitivity of marbles can be characterised by the irreversible length change of samples after heating under thermohygric conditions as residual strain. This residual strain is a non-reversible deterioration and caused by microcracking induced by a pronounced anisotropy of the thermal dilatation coefficient of calcite. In brittle materials like marble, cracking and crack growth or friction on crack surfaces are accompanied by release of acoustic waves. The analysis of these acoustic emissions can give aSince ancient times, marble has been the preferred material for monuments, sculptures, Ornaments and architecture. Though the stone is often a Chosen material, long-term exposure of marble results in cumulative deterioration of the rock fabric. The rate and extent of deterioration depends on the rock fabric and the climatic conditions. Besides the thermal vulnerability of marble, a combination of thermal and hygric fluctuation accelerates the deterioration process. The weathering sensitivity of marbles can be characterised by the irreversible length change of samples after heating under thermohygric conditions as residual strain. This residual strain is a non-reversible deterioration and caused by microcracking induced by a pronounced anisotropy of the thermal dilatation coefficient of calcite. In brittle materials like marble, cracking and crack growth or friction on crack surfaces are accompanied by release of acoustic waves. The analysis of these acoustic emissions can give a deeper insight into the deterioration mechanism of marble. In this study, acoustic emissions of thermohygric treated marble were analysed and correlated with ultrasonic velocities, thermal dilatation and residual strains. Therefore, different types of calcitic marble were cyclically heated from 20 °C to 90 °C and after equilibration of the samples cooled down again to 20 °C. While the first cycles were performed under dry conditions, the following were executed in a humid environment. The analysis of acoustic emissions enables one to determine when cracking occurs during the thermal treatment. It is also possible to differentiate microcracking from internal friction. Furthermore, the evolution of Deterioration can be estimated based on ultrasonic velocities. The combination of acoustic Methods and strain measurement gives an insight into the disintegration mechanism and Supports the development of prevention strategies.zeige mehrzeige weniger

Volltext Dateien herunterladen

  • 2020 Pirskawetz et al Stone 2020.pdf
    eng
  • 2020_Priskawetz et al_Stone 2020_Deckblatt_Impressum_Inhaltsverzeichnis.pdf
    eng

Metadaten exportieren

Weitere Dienste

Teilen auf Twitter Suche bei Google Scholar
Metadaten
Autoren/innen:Stephan Pirskawetz, J. Menningen, S. Siegesmund
Persönliche Herausgeber/innen:S. Siegesmund, B. Middendorf
Dokumenttyp:Beitrag zu einem Tagungsband
Veröffentlichungsform:Verlagsliteratur
Sprache:Englisch
Titel des übergeordneten Werkes (Englisch):MONUMENT FUTURE: Decay and Conservation of Stone. - Proceedings of the 14th International Congress on the Deterioration and Conservation of Stone
Jahr der Erstveröffentlichung:2020
Organisationseinheit der BAM:7 Bauwerkssicherheit
7 Bauwerkssicherheit / 7.1 Baustoffe
Verlag:mdv Mitteldeutscher Verlag GmbH
Verlagsort:Halle (Saale)
Erste Seite:185
Letzte Seite:190
DDC-Klassifikation:Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau
Freie Schlagwörter:Acoustic emission; Cracking; Marble; Residual strain; Weathering sensitivity
Themenfelder/Aktivitätsfelder der BAM:Infrastruktur
Infrastruktur / Sicherheit und Lebensdauer von Bauwerken
Veranstaltung:14th International Congress on the Deterioration and Conservation of Stone
Veranstaltungsort:Göttingen, Germany
Beginndatum der Veranstaltung:07.09.2020
Enddatum der Veranstaltung:12.09.2020
ISBN:978-3-96311-172-3
Verfügbarkeit des Dokuments:Datei im Netzwerk der BAM verfügbar ("Closed Access")
Datum der Freischaltung:07.01.2021
Referierte Publikation:Nein