Geotechnical aspects of earthen construction materials

Earthen construction and soil-based construction materials (SBCMs) are expanding areas of interest worldwide. They offer the potential for low carbon and embodied energy, sustainability through recycling and an alternative to high energy materials such as fired masonry. The materials that are generally used in earthen construction can be identified as manufactured unsaturated soils. Until recently, however, these materials have rarely been studied using a geotechnical approach, and there is a general lack of recognition of the key mechanisms at work mechanically and hydraulically. In this paper we review geotechnical aspects of soil-based construction materials examining the effects of suction and environmental conditions, and demonstrating behaviour in shear, compression and fracture. We cover materials which are both unstabilised, where the primary source of strength is suction, and materials which are stabilised with cement, lime or fibres. The review is backed up by experimental results from laboratory and field testing undertaken over a number of years at Durham and UWA. © The authors and ICE Publishing: All rights reserved, 2015.