scispace - formally typeset
Journal ArticleDOI: 10.1080/15583058.2019.1626513

A ‘Sandwich’ Specimen Preparation and Testing Procedure for the Evaluation of Non-Structural Injection Grouts for the Re-Adhesion of Historic Plasters

04 Mar 2021-International Journal of Architectural Heritage (Taylor & Francis)-Vol. 15, Iss: 3, pp 455-466
Abstract: Non-structural injection grouting aims to stabilise delaminated plaster by introducing in the void, typically between delaminated plaster layers, a compatible adhesive material with bulking propert...

... read more


5 results found

Open accessJournal ArticleDOI: 10.1007/S12520-021-01409-X
Abstract: The use of mortars and plasters has been widespread in many cultures for thousands of years and these materials are found in the vast majority of built cultural heritage. They play a crucial role in the preservation of immovable heritage and must be taken into great consideration when conserving historical buildings. Plasters and mortars have been extensively studied from a chemical and mineralogical point of view. The main causes and mechanisms of damage and deterioration are understood and various methods and materials have been developed for their preservation. Treatment development, testing and evaluation in the laboratory, under controlled conditions, has produced a high level of knowledge. However, there is a divergence between the results of academic-scientific studies and practice in the field. Laboratory studies typically tackle only a few variables at the time and the results cannot always be directly applied to address the complex problems that restorers face in their daily work practice. In addition, in situ conservation-restoration is extremely challenging because many of large number of variables involved cannot be controlled or modified. Following a description of the ideal “value-based” conservation process, this compilation work discusses aspects related to understanding deterioration mechanisms and planning of preventive and remedial interventions in a way that may be useful to update conservators-restorers on the status of scientific research in this field, and to guide conservation-scientists to identify unresolved issues, which require future research efforts.

... read more

17 Citations

Journal ArticleDOI: 10.1080/15583058.2020.1731629
Abstract: Lime-based grouts are usually applied for the consolidation and strengthening of historic structures. In the case of architectural surfaces (renders, plasters, murals, wall mosaics), the testing pr...

... read more

Topics: Consolidation (soil) (53%), Lime (51%)

7 Citations

Open accessJournal ArticleDOI: 10.3390/MA13153360
29 Jul 2020-Materials
Abstract: Injection-grout density is an important parameter when its additional weight leads to consolidated decorative plasters becoming damaged. This is especially evident in larger detached areas. In this study, thin-walled soda-lime-borosilicate glass microspheres were used as a density-reducing constituent in hydrated lime grout mixtures. The normal density grout composition-one volume part hydrated lime and three volume parts inert limestone filler with 0.5% of the polycarboxylate ether-based superplasticiser-was modified with partial substitution of the limestone filler with lightweight glass microspheres. The following volumetric proportions between limestone filler and glass microspheres were used: 100%:0%, 67%:33%, 50%:50%, 33%:67%, and 0%:100%. With the increase of the glass microspheres' volume, the density of the grout is gradually reduced. Furthermore, there is a decrease in the stability and injectability of fresh grout. In its hardened state, the grout's strength again reduces gradually, but there is no significant change in the grout's water absorption and water-vapour resistance. The resistance of the grout to freezing-thawing and heating-cooling cycles using distilled water or salt solution is highly improved when the microspheres are present.

... read more

Topics: Grout (63%), Glass microsphere (55%), Lime (51%)

4 Citations

Journal ArticleDOI: 10.1080/00393630.2020.1761179
Abstract: The design and evaluation of site-specific injection grouts for the stabilisation of delaminated wall paintings is often challenging to perform in situ, due to constraints such as time, availabilit...

... read more

2 Citations

Open accessJournal ArticleDOI: 10.3390/MA14195585
26 Sep 2021-Materials
Abstract: Dry hydrated lime is an air binder often used in architectural injection grouts. This study compared the influences of three commercially available dry hydrated limes on the injection grouts’ workability and mechanical properties. The main differences between the limes were in their chemical and mineralogical composition and Blaine specific surface area. The grouts were composed of dry hydrated lime, finely ground limestone filler, water, and super plasticiser. Subsequent results obtained revealed that the Blaine specific surface area is not directly related to the fresh grout properties. Grain size distribution and shape of lime particles and their aggregates in the water suspension are key parameters influencing the following fresh grout properties: fluidity, injectability, the mixture’s stability, and water retention capacity. However, the lime injection grouts’ mechanical strengths were higher in relation to an increase in the content of portlandite and the Blaine specific surface area of the dry hydrate.

... read more

Topics: Lime (56%), Grout (52%)

16 results found

Journal ArticleDOI: 10.1016/J.CONBUILDMAT.2007.12.003
Abstract: Old fortresses near the coast of Lisbon have been originally rendered with very durable lime mortars, sometimes showing pozzolanic reactions (Silva A. Caracterizacao de argamassas antigas – casos paradigmaticos (in Portuguese). Lisbon: LNEC; October 2002. Cadernos Edifi´cios, No. 2. p. 87–101; Pinto J, Silva A. Lime mortars with pozzolans. The S. Juliao da Barra and Ericeira case studies (in Portuguese). In: 3rd ENCORE, Encontro sobre Conservacao e Reabilitacao de Edifi´cios. Lisbon: LNEC; May 2003), but their very severe environmental conditions – salty atmosphere and sea water close to foundations and walls, mechanical action of the waves, hot sun and temperature variations, strong wind – and also some lack of knowledge concerning maintenance and conservation techniques, produced the deterioration of these renders and the need for their substitution. The best options were thought to be lime mortars with pozzolanic additions. Because of the lack of experience with modern pozzolanic mortars on sea environment, it was decided to carry out experimental applications on one of the Fortresses’ walls of renders with different pozzolanic additives and of some comparison mortars with known performance. Tests were carried out in situ and in laboratory and one of the formulations was chosen for application as a substitution render of the Fortress’s walls.

... read more

Topics: Pozzolan (52%)

94 Citations

Abstract: A combined reaction of hydration and carbonation takes place in hydraulic lime and lime-pozzolana mortars. Hydration reactions are the first reaction and carbonation of lime is the complementary reaction in the strength gain. Competition between these two reactions can occur in lime-pozzolana mortars if the pozzolanic material has low reactivity with lime, leading to the consumption of lime by carbonation reaction. The degree and the order of these reactions are strongly influenced by the moisture content. Hydration reactions are enhanced under moist conditions while carbonation is delayed. Curing under dry conditions does not sufficiently increase their strength because the hydration reactions are slowed down or even terminated by the full carbonation of lime in lime-pozzolana mortars. The consequence of this on the mechanical properties of the mortars is remarkable while the same impact is not observed in their porosity. Such mortars require moist conditions to ensure sufficient strength development.

... read more

Topics: Hydraulic lime (72%), Carbonation (65%), Lime (59%) ... read more

55 Citations

Journal ArticleDOI: 10.1016/J.NANO.2009.09.005
Yinsong Wang1, Shaoli Tu2, Rongshan Li1, Xiaoying Yang1  +3 moreInstitutions (3)
Abstract: The purpose of this study was to prepare cholesterol succinyl chitosan anchored liposomes (CALs) and to investigate their characterization, physical stability, and drug release behavior in vitro. Three cholesterol succinyl chitosan (CHCS) conjugates with different substitution degrees (DS) of the cholesterol moiety were synthesized and used as the anchoring materials to coating on the liposome surface by the incubation method. CALs were almost spherical and had a classic shell-core structure. Compared with plain liposomes and chitosan-coated liposomes (CCLs), CALs had larger sizes, higher zeta potentials, and better physical stability after storage at 4 ± 2°C and 25 ± 2°C. Epirubicin, as a model drug, was effectively loaded into CALs and exhibited the more sustained release in both phosphate buffer solution (pH 7.4) and 1% (vol/vol) aqueous fetal bovine serum compared to plain liposomes and CCLs. From the Clinical Editor Cholesterol succinyl chitosan anchored liposomes (CAL) as delivery vehicles are characterized in this work, including their physical stability and drug release behavior in vitro. Epirubicin as a model drug, was effectively loaded into CALs, and exhibited sustained release behavior both in phosphate buffer solution (PBS, pH 7.4) and 1% (V/V) aqueous fetal bovine serum (FBS).

... read more

Topics: Drug carrier (58%), Liposome (53%)

46 Citations

Journal ArticleDOI: 10.1016/J.CONBUILDMAT.2014.02.020
Abstract: When designing repair mortars, it is important to consider all its components such as the binder and the aggregates since they have a great influence on the mortar’s final properties. The binder, and the aggregates' angularity and chemical composition determine the properties of the mortar, properties critical for a good compatibility and durability of a restoration intervention. In this article, some mineral repair mortar design philosophies are approached, followed by the requirements set for a plastic repair mortar for stone. Up to which point is an intervention compatible? An answer was found when examining several articles that discuss the compatibility tolerance plane. This article aims to give the reader a hands-on approach in mineral repair mortar design and how this can be used to make a mineral repair mortar more compatible with the substrate.

... read more

Topics: Mortar (62%)

38 Citations

Journal ArticleDOI: 10.1016/J.CONBUILDMAT.2013.09.006
L.C. Azeiteiro1, Ana Velosa1, H. Paiva1, Pedro Q. Mantas1  +2 moreInstitutions (2)
Abstract: A study was conducted on the development of lime based grouts for consolidation of renders and plasters detached from the support. The aim is to develop grouts that should be compatible with the pre-existing materials and allow the restoring of the adherence of coatings to the background. Special attention was paid to the rheological behaviour of the grouts and to other features of the fresh state. The role of components such as binders, aggregates and admixtures used in the formulations was tested through an outlined series of mechanical and physical tests. In terms of hardened state properties, a set of basic requirements (related to strength and capillarity) were evaluated and a test for adhesion loss measurement was developed in order to test the ability of developed grouts to restore adhesion of coating layers. The rheological behaviour was evaluated through a distinct procedure, which involved the test with a specific speed profile (dwell profile). The dwell profile allows studying the rheological behaviour along measuring time, making possible to observe changes in rheological parameters in mortar suspensions, through the measurement of flow curves along the time test. The dwell profile allowed obtaining the rheological parameters (viscosity and yield stress) according to the Bingham model. Grouts based on lime, fine sand and metakaolin together with the right amount of water and admixtures were developed and adjusted in order to be used in consolidation works of old renders.

... read more

30 Citations

No. of citations received by the Paper in previous years