Investigative methods for the characterisation of historic mortars. Part 2: Chemical characterisation

Title: Investigative methods for the characterisation of historic mortars. Part 2: Chemical characterisation
Author(s): RILEM TC 167-COM, B. Middendorf, J. J. Hughes, K. Callebaut, G. Baronio, I. Papayianni
Paper category : journal
Serial title: Materials and Structures
Abreviated Serial title: Mater. Struct.
ISSN: 1359-5997
Publisher: RILEM Publications SARL
Volume: 38
Issue: 282
Issue date: 2005-10-01
Publication year: 2005
Pages: 771 - 780
Total Pages: 10
Nb references: 16
Language: English

Abstract: In addition to the mineralogical characterisation of components of binder and aggregate in historic mortars, it is sometimes necessary to perform a chemical analysis on the materials in historic mortars.
Acid dissolution/separation of binder from aggregate is the simplest method, and allows the determination of the chemical composition of the acid-soluble binder and, after separation, information on the mortar’s aggregate.
It is limited, when aggregate is acidsoluble.
A range of significant analysis can be made including for soluble silica that relates to hydrated calcium silicates in the binder, and thus the hydraulicity of the binder.
Other wet chemical analyses can be performed on the acid filtrate for soluble oxides of Fe, Al, Ca, Mg, S, Na and K.
There may also be a requirement for the identification of organic substances, pigments and salts within an historic mortar.
Chemical analysis forms a 2nd part of a possible scheme of characterisation of historic mortars that is presented as a flowchart.
Chemical analysis also satisfies requirements for information input to conservation, repair and restoration works on historic buildings for the choice of compatible replacement materials.
Corroboration of evidence of identification and quantification for chemical composition is best supported by a combination of methods, including mineralogical analysis methods.
All methods of characterisation require qualified and experienced people to carry out the analyses.

Online publication: 2005-02-15
Classification: RILEM Technical Committees
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/14282