Injection grouting is conservation treatment commonly used to fill voids and cracks and reattach separated historic plasters, wall paintings, and mosaics to architectural substrates. On a larger scale, structural injection grout is often used to fill cracks and voids and reinforce masonry constructions. The effectiveness of these treatments is largely dependant upon the physical and chemical properties of the grout. For example, the rheological or “flowing” characteristics of the grout determine its ability to fill-in open spaces. In conservation applications, a grout must maintain adequate bond (i.e. minimal shrinkage) after curing and have mechanical strength and moisture transmission properties compatible with the materials being treated. Factors such as these complicate the process of finding or formulating a suitable grout.
In 2013, after a multi-year research project, the Getty Conservation Institute released a manual with procedures for testing lime-based hydraulic injection grouts for the conservation of architectural surfaces. Now, nine supplemental videos illustrating the laboratory procedures recommended in the manual have been released. Together, these resources demonstrate laboratory tests measuring the properties of injection grouts, including injectability, splitting tensile strength, and capillary water absorption, providing reliable tools for conservators and conservation scientists to assess and compare different grouts in the laboratory and field.
To download the manual or view the videos visit, http://www.getty.edu/conservation/publications_resources/pdf_publications/evaluation_grouts.html