A lime-based grouting material for the repair of earthen structures
- The repair of earthen structures is not an easy task. Earth as a construction material has comparatively weak mechanical properties. It is also susceptible towards liquid water, were it can lose cohesion very quickly if certain moisture contents are exceeded. Repair concepts of structures built with such materials are therefore challenging. Historical earthen structures often exhibit damages in form of extensive cracking, which may have been caused by static or dynamic loads. Frequently these cracks are insufficiently or inappropriately repaired because of lack of knowledge and / or technology. In particular, the behaviour of crack repair by grouting poses a challenge in earthen materials and demands specific requirements for the grouting mortar, such as low water content, good water retention, low shrinkage. Grouting materials require additional specifications such as compatible strengths and Young’s modulus as well as good adhesion to the earthen substrates. In addition, grouts haveThe repair of earthen structures is not an easy task. Earth as a construction material has comparatively weak mechanical properties. It is also susceptible towards liquid water, were it can lose cohesion very quickly if certain moisture contents are exceeded. Repair concepts of structures built with such materials are therefore challenging. Historical earthen structures often exhibit damages in form of extensive cracking, which may have been caused by static or dynamic loads. Frequently these cracks are insufficiently or inappropriately repaired because of lack of knowledge and / or technology. In particular, the behaviour of crack repair by grouting poses a challenge in earthen materials and demands specific requirements for the grouting mortar, such as low water content, good water retention, low shrinkage. Grouting materials require additional specifications such as compatible strengths and Young’s modulus as well as good adhesion to the earthen substrates. In addition, grouts have to be sufficiently flowable to fill small cracks and voids without segregation or bleeding. Therefore, the rheological behaviour has to be well understood and controlled to gain the desired effects. The repair of cracks in earthen buildings is traditionally done by stuffing manually mortar into the gap. Naturally, this method is only usable for cracks with large widths. Another disadvantage is that cracks going through thicker walls cannot be completely reached by the tools used for stuffing the mortar into the crack. Lime based grouts for earthen materials were usually used for re-attachment of plasters but less for structural reasons. Due to the nature of earthen materials grouts based on formulated or hydraulic lime (according to the definition in EN 459-1) have to meet considerable demands on a variety of properties, which are related to compatibility, durability and in particular to the ability of being injected. The goal of this study was to create a grout, which can be used to re-establish structural continuity in cracked earthen masonry or other massive earth walls (rammed earth and cob) with the focus on grouting cracks. The grout material was based on hydrated lime (calcium hydroxide) with additions of pozzolana and lime stone filler.…
Autor*innen: | U. Müller, Lorenzo Miccoli, Patrick Fontana |
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Dokumenttyp: | Beitrag zu einem Tagungsband |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Lehm 2016 - Proceeding of the 7th International Conference on Building with Earth |
Jahr der Erstveröffentlichung: | 2016 |
Herausgeber (Institution): | Dachverband Lehm e. V. |
Verlag: | Eigenverlag Dachverband Lehm e. V. |
Verlagsort: | Weimar |
Erste Seite: | 1 |
Letzte Seite: | 8 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten |
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau | |
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Sanitär- und Kommunaltechnik; Umwelttechnik | |
Freie Schlagwörter: | Building Materials; Earth construction; Grout mortar; Historical buildings; Hydraulic lime; Repair |
Veranstaltung: | Lehm 2016 - 7th International Conference on Building with Earth |
Veranstaltungsort: | Weimar, Germany |
Beginndatum der Veranstaltung: | 12.11.2016 |
Enddatum der Veranstaltung: | 13.11.2016 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 24.01.2017 |
Referierte Publikation: | Nein |