Call edition 2012
A new edition of the Prize of the Belgian Development Cooperation has been launched. This call is open until March 31st, 2011. You can read in the regulations whether you comply with the criteria for participation.
Many developing countries are confronted with the need to provide suitable and yet affordable housing for their rapidly growing populations. Classic building materials are quite expensive, however, and their production is characterized by the intense use of unrenewable raw materials and a significant use of energy. Throughout the world, recent years have seen an increasing interest in durable building materials whose production demands a minimum of energy, causes little pollution, and whose cost is low.
In many developing countries, Egypt among them, most of the houses in the villages are constructed of sun-dried mud bricks, made up of clayey loam mixed with sand and straw. But these bricks have a low mechanical strength and limited resistance to torrential rain and intense heat. As an alternative, blocks made of compressed earth (‘compressed earth blocks’ or CEB for short) have recently been developed. These blocks offer many advantages in terms of environment, cost and technical properties, which include good thermal and acoustic insulation.
In a scientifically-based and systematic way the author has analysed the various parameters that influence the rather complex production process, which should ultimately permit optimum control of this process. Research has been carried out into optimum moisture levels, the pressure to be applied to the earth in the moulds, and the types of stabilization that can be used to increase compression and durability. To produce this stabilization the following are appropriate: stabilization with lime, the addition of palm fibres, stabilization with bituminous emulsions and coatings with a mixture of lime and natrium chloride.
This work makes a fundamental contribution to the further use of compressed earth blocks and thus contributes to the raising of living standards of the less well-off in developing countries.
report by Prof. Dr. Ir. Luc Taerwe, Department of Structural engineering, Universiteit Gent, Belgium