The project aims to examine the load-bearing behaviour of earth block masonry (EBM). The work will look at failure mechanisms to ensure the design complies with the relevant masonry standard, DIN EN 1996/NA.
The research institute Bundesanstalt für Materialforschung und –prüfung (BAM), which is part of the German Federal Ministry for Economic Affairs & Energy, is involved in the project. The Technical University of Darmstadt and ZRS Ingenieure are also involved and the project is being given both technical and financial support by the Deutsche Bundesstiftung Umwelt (DBU).
Ecological construction is becoming ever more significant in the light of the ever-increasing need for housing, said BAM. New apartments and houses must be as resource-saving as possible. “As a natural building material, earth offers numerous advantages,” said Dr Marc Thiele, project leader in the Buildings and Structures Division at BAM. Earth requires a minimum amount of primary energy, is available almost everywhere and is 100% recyclable, he said. Due to its high mass, it also offers excellent sound insulation properties and is non-flammable.
The project aims to expand the already extensive knowledge on the load-bearing behaviour EBM so that a simplified design is possible. Preliminary studies have revealed that the load-bearing behaviour and bearing capacity of EBM are comparable to those of conventional masonry. BAM said that that the earth blocks and mortars available on the market and produced in factories are of the same quality as conventional bricks and mortars.
The scope of the planned project will extend the existing experimental investigations on the blocks and mortar and will also include extensive investigations on building elements. The results will be used to determine building material properties - strength, modulus of elasticity, deformation properties - and their statistical characteristic values. Subsequently, the required reliability level can be calibrated and thus integrated into the safety format of current masonry standards.
Earlier research work on earth construction – including at BAM – led to the introduction of product standards in Germany for earth blocks, earth mortar and earth ‘plasters’ in 2013 and for loam boards in 2018. Earth plasters they have already been integrated into the general application standard for plaster mortars. Earth blocks and earth mortar must also achieve this to enable the broad application of EBM based on the generally applicable design regulations, said BAM.