Abstract

In order to check the suitability of soil to be used as construction materials for earth construction, its geotechnical properties are required to be assessed. The purpose of this study is to review previously published studies’ soil samples and compare them with soil suitability criteria and for selecting suitable soil for earth construction. The geotechnical properties of soil samples used in previous studied were compiled and compared with various requirements to ascertain their suitability for construction purposes. Eighty-nine (89) studies in all were consulted and useful data were found in fifty-two (52) of them. Five geotechnical properties of soil were reviewed and analysed. These properties are particle size distribution, Atterberg limits, specific gravity, maximum dry density and optimum moisture content. Based on the values of soil properties found in literature, recommendations were made for the suitability of different soil samples for three main techniques (adobe, rammed earth and compressed earth blocks) application in earth construction, while other soil samples were found to be outside the recommendations. It was found that some of the earth construction techniques which were adopted in the previous studies are different from the recommended techniques. It was also observed that some of the soil samples found to be suitable for a particular property test were unsuitable for the other property tests. The study concludes that determining the suitability of the soil for earth construction is important and any soil that is found unsuitable should be enhanced with stabilisers before use.

Keywords: Adobe blocks; Compressed earth blocks; Earth construction; Geotechnical properties; Soil suitability; Rammed earth