A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Restoration of ancient gypsum-based plasters: Design of compatible materials
https://orcid.org/0000-0001-9402-0501
Abstract In this paper, the process of design and evaluation of compatible materials to partially or completely substitute damaged interior walls and ceilings coatings made of gypsum-based plasters is presented and the results obtained are discussed. The methodology used comprised the definition of quantitative requirements to be accomplished by the new materials, based on previous works of the authors with characterization of an extensive set of samples of historic buildings. It was concluded that there is need to develop three different restoration materials, one for each family of plaster elements: thin-layer finishing plasters (L), elements moulded on site (M) and precast decorative elements (P). The physical and mechanical properties of seven mixes based on gypsum and lime, with addition of other components, were determined and allowed concluding that the binder proportions (gypsum: lime) is the most influential factor. Higher gypsum content leads to stiffer materials, less shrinkage and higher absorption coefficients than in lime-based mixes. The formation of micro cracks was pointed out as a possible cause for the decrease of flexural strength and water vapour permeability values of the M mixes. The comparison of the results obtained with the compatibility requirements allowed finding well-suited restoration materials for thin-layer coatings and precast elements. The mixes for moulded on site elements revealed to be the less balanced, and some adjustments are advised.
Highlights Adequate methodology allowed the development of compatible restoration materials. Solutions for thin-layers (L), moulded on site (M) and precast (P) plasters are proposed. Gypsum and gypsum-lime based repair mixes are defined and characterized. The binders proportions greatly influence the physical and mechanical properties. Compatible materials were found for L and P elements; M mixes need further settings.
Restoration of ancient gypsum-based plasters: Design of compatible materials
https://orcid.org/0000-0001-9402-0501
Abstract In this paper, the process of design and evaluation of compatible materials to partially or completely substitute damaged interior walls and ceilings coatings made of gypsum-based plasters is presented and the results obtained are discussed. The methodology used comprised the definition of quantitative requirements to be accomplished by the new materials, based on previous works of the authors with characterization of an extensive set of samples of historic buildings. It was concluded that there is need to develop three different restoration materials, one for each family of plaster elements: thin-layer finishing plasters (L), elements moulded on site (M) and precast decorative elements (P). The physical and mechanical properties of seven mixes based on gypsum and lime, with addition of other components, were determined and allowed concluding that the binder proportions (gypsum: lime) is the most influential factor. Higher gypsum content leads to stiffer materials, less shrinkage and higher absorption coefficients than in lime-based mixes. The formation of micro cracks was pointed out as a possible cause for the decrease of flexural strength and water vapour permeability values of the M mixes. The comparison of the results obtained with the compatibility requirements allowed finding well-suited restoration materials for thin-layer coatings and precast elements. The mixes for moulded on site elements revealed to be the less balanced, and some adjustments are advised.
Highlights Adequate methodology allowed the development of compatible restoration materials. Solutions for thin-layers (L), moulded on site (M) and precast (P) plasters are proposed. Gypsum and gypsum-lime based repair mixes are defined and characterized. The binders proportions greatly influence the physical and mechanical properties. Compatible materials were found for L and P elements; M mixes need further settings.
Restoration of ancient gypsum-based plasters: Design of compatible materials
https://orcid.org/0000-0001-9402-0501
Abstract In this paper, the process of design and evaluation of compatible materials to partially or completely substitute damaged interior walls and ceilings coatings made of gypsum-based plasters is presented and the results obtained are discussed. The methodology used comprised the definition of quantitative requirements to be accomplished by the new materials, based on previous works of the authors with characterization of an extensive set of samples of historic buildings. It was concluded that there is need to develop three different restoration materials, one for each family of plaster elements: thin-layer finishing plasters (L), elements moulded on site (M) and precast decorative elements (P). The physical and mechanical properties of seven mixes based on gypsum and lime, with addition of other components, were determined and allowed concluding that the binder proportions (gypsum: lime) is the most influential factor. Higher gypsum content leads to stiffer materials, less shrinkage and higher absorption coefficients than in lime-based mixes. The formation of micro cracks was pointed out as a possible cause for the decrease of flexural strength and water vapour permeability values of the M mixes. The comparison of the results obtained with the compatibility requirements allowed finding well-suited restoration materials for thin-layer coatings and precast elements. The mixes for moulded on site elements revealed to be the less balanced, and some adjustments are advised.
Highlights Adequate methodology allowed the development of compatible restoration materials. Solutions for thin-layers (L), moulded on site (M) and precast (P) plasters are proposed. Gypsum and gypsum-lime based repair mixes are defined and characterized. The binders proportions greatly influence the physical and mechanical properties. Compatible materials were found for L and P elements; M mixes need further settings.
Restoration of ancient gypsum-based plasters: Design of compatible materials
Freire, Maria Teresa (author) / Veiga, Maria do Rosário (author) / Santos Silva, António (author) / de Brito, Jorge (author)
2021-03-08
Article (Journal)
Electronic Resource
English
Cracking of Ancient Gypsum Plasters
| British Library Conference Proceedings | 2002
| Springer Verlag | 2014
| Engineering Index Backfile | 1965
Gypsum and anhydrite building plasters
Engineering Index Backfile | 1944