Structural Grouting Materials

The study and testing of grouts has been a topic of interest for the conservation community since the early 1970s. The compatibility of lime- or earth-based grouting formulations with adjacent materials has been considered in work carried out by the Conservation Institute at several sites, but studies considering the efficiency of this method for seismic stabilization or the nature of the impact of a seismic event on the grout and/or its relationship with the original materials and structure are lacking. In an effort to address this issue, the Earthen Architecture Initiative team undertook a multidisciplinary program to analyze different methods of repairing seismically induced cracks.

In 2006 the Escuela de Ciencias e Ingeniería at the Pontificia Universidad Catolica del Peru (PUCP) started testing and bibliographical research to identify adequate structural grouting materials for adobe walls using locally available soil. The Conservation Institute then provided financial and technical support for a second research phase addressing both engineering and conservation issues. The objective was to compile information, conduct research, and perform laboratory testing to identify and evaluate grouting materials that are compatible with original materials, structurally effective, and result in minimal impact on original fabric during a seismic event.

In August 2007 the Earthen Architecture Initiative hosted an experts meeting in collaboration with PUCP in Lima to share knowledge and evaluate laboratory testing protocols and methodologies for the study of structural grouting in seismic areas. Meeting summary notes are available in the Resources section. Meeting participants have continued to exchange information, and a second experts meeting was held in July 2008 in Bath, England, as part of the VI International Conference on Structural Analysis for Historical Constructions.