Behaviour of the soils for the adobe manufacture

Abstract

The constant demand in Chile for adobe construction, specially in those areas far away from industrialized urban centers, makes it necessary to put up to date the actual recommendations for building with this material. That is the consequence of the experience of some builders who, in the past, have succeded in using it. Therefore a standard is necessary to establish the proper proceeding to build safely with adobe taking advantage of its qualities, the use of adhitives and obviously to describe the procedure for desing and calculation of structures with an empirical support. Our first step on that direction has been our experimentation in RlLEM samples with the respond of the dry soil mortar when changing the values of clay, mud, sand and water in the mix. The results of this study may be resumed in the following four basic recommendations: 1. The use of floors with a mud/clay ratio near to one and a sum between 35/45 % of the total. 2. The sand content of the soil should be between 55/65 %. 3. The optimum amount of water for the mix depend on the composition of the land and on the technology used. In our case, such an optimum is placed in the liquid limit, plus one third of the plasticity rate of the soil. We must point out the great importance of this factor in all the different combinations performed in our study. It would be a great advantage to be able to control it, however, at a kandiwork level, it has not been possible. 4. In order that the dried will reach satisfactory and uniform mechanical characteristics, it is necessary that: i) The soil should be macerate in a saturated state from 48 to 72 hours. ii) Before filling the moulds it is necessary to proceed to a complete mix of the mass in order to prevent that the slides of clay might be ordered according to electrical atractions.