243-SGM : Specifications for non-structural grouting of historic masonries and architectural surfaces

Technical Committee 243-SGM


General Information

Chair: Dr. Caspar J.w.p. GROOT
Deputy Chair: Dr. Jan VALEK
Activity starting in: 2010
Activity ending in: 2017
Cluster E

Subject matter

The establishment of general performance criteria and recommendations dealing with
   (i) the materials choice and the application technique  of non-structural grouts for restoring and repairing pre-existing masonry walls (e.g. to solve permeability problems)
   (ii) the materials choice and application technique forthe conservation historic of architectural surfaces ( e.g. mosaics, frescoes, plasters, natural stone).

Focus on materials properties, compatibility aspects and application techniques.

Works will take into account:
1) Requirements for non-structural grout application and surface repair, depending on their function
2) Fundamental parameters for grout and surface repair design
3) Testing methods for measuring those parameters.
4) Methodologies and techniques for the control of the execution operation
5) Performance evaluation

Terms of reference

The objectives will be achieved by reviewing and comparing the results of recent research and practical experiences, at international expert level.
The time needed for achieving deliverables of practical relevance to the research world and the building practice is rated at 4-5 years.

The regular and correspondent members to be recruited are well known experts with outstanding academic as well as practical experience in the field of restoration of masonry structures. Several of them participated in former and current RILEM Committees, whose subject is relevant to the proposed one.

Those Committees are:
 - Technical Committee 167-COM: Characterization of historic mortars with respect to their repair
 -  Technical Committee 203-RHM: Repair mortars for historic masonry
 -  Technical Committee 216-SAM: Strategies for the assessment of historic masonry structures with NDT

Detailed working programme

The T.C. should work along the following lines:
 -  definition of problems related to the need for non-structural grouting and surface repair
 -  definition of the various functions of a grout and surface repair material
 -  general classification of grouts and surface repair materials
 -  requirements for design, depending on the function of the repair material
 -  identification of testing methods for measuring those parameters
 -  identification of suitable methodologies and techniques for the control of the application quality (before, during, after), including surveys of walls and surfaces where the repairs are to be applied and "in situ" tests
 -  identification of machinery requirements application
 -  quality control procedures and acceptability limits

Technical environment

 -  Technical Committee COM: Characterization of historic mortars in respect to their repair
 -  Technical Committee 203-RHM: Repair mortars for historic masonry
 -  Technical Committee 216-SAM: Strategies for the assessment of historic masonry structures with NDT
 -  Technical Committee "Design and application of hydraulic grouts for repair and strengthening of historic masonry structures". This new RILEM TC on structural grouting will be chaired by to be proposed by dr Androniki Miltiadou-Fezans.
Contact with this RILEM TC will be established through a double membership of  prof Luigia Binda, who will be member of both TC’s. Overlap of TC-activities may easily be avoided, as the non-structural grouting is focused on the solution of permeability problems in masonry (moisture transport, leakage), while the other TC is focused on the structural application of grouts; moreover, the other part of the TC’s work on surface repair as well is a specific field of repair not in competition with structural grouting.

Expected achievements

- A general guideline dealing with (a) the methodology of choosing, preparing and applying non-structural grouts and reattachment materials for restoration and repair and (b) the methodology for controlling the application techniques (c) the evaluation of the performance.

- A state-of-the-art report dealing with:
  a)  the definition of cases, where non-structural grouting and surface reattachment materials  could be considered as a possible intervention,
  b)  the classification of the applied materials (properties)  in relation to their function,
  c)  the most important standard methods recommended for characterization of the applied materials
  d)  the most important standard methods recommended for the control of the application techniques of the applied materials taking into account the substrate characteristics
  e)  experimental and in situ data on the application of non-structural grouts and reattachment materials

Group of users

The target groups are practitioners like architects, engineers, industry and specialized contractors. Other target groups are cultural public and private organisations (Ministries or State Departments, Archaeological Schools etc.) involved in the preservation of the cultural heritage and bearing a role in supervising such operations. For all those groups, guidelines dealing with the methodology of choosing, preparing, applying and controlling grouts and reattachment materials for restoration and repair are meant to avoid common mistakes of the past. The most important impact is to be found in the more rational and controlled preservation of the masonry heritage through the application of compatible, durable and sustainable interventions.

Specific use of the results