Assessment of the injection of grouts to repair cracks in rammed earth

Abstract

Rammed earth constructions are known for their high seismic vulnerability, which menaces their preservation and puts in risk the life of millions of people living in regions with important seismic hazard. The poor conservation condition of many of these constructions largely contributes for the aforementioned situation. The presence of cracks is one common type of damage occurring in the walls, which debilitates their structural behaviour both for in-plane and out-of-plane loading. The injection of grouts has been studied recently as a solution to repair this type of damage. However, the repair effectiveness of this technique needs further research. This paper presents an experimental program, where the effectiveness of the injection of a mud and a commercial grout base on hydraulic lime for repairing cracks in rammed earth is compared. Diagonal compression test were carried out on wallets before and after repair, where the response was monitored with Digital Image Correlation (DIC). Furthermore, sonic tests were used as a technique to assess the repair efficiency by non-destructive means. In general, both types of grouts presented similar performance.