Rammed earth sustainability and durability in seismic areas as a building material

Abstract

Abstract Rammed earth is one of the oldest materials of the world and has been used as a building material for centuries due to its availability, low cost benefits, auto-construction and bioclimatic capabilities to sustain extreme weathers. Rammed earth and adobe housing are constructed in earthquake prone areas around the world due to these benefits. These earthen materials are used to mainly build load carrying walls with light cover of timber. These auto-constructed buildings are extremely vulnerable to earthquake shaking due to its heavy mass, strength degradation through time and lack of structural integrity among elements. This is a natural and sustainable material that deserves to be investigated in order to be used again as a main construction material against masonry and concrete housing. It is needed to understand its behaviour under different loading conditions to identify the components that convert it into a highly vulnerable material. The present investigation focuses on the durability of rammed earth as a construction material of housing located in seismic areas of Mexico. It is presented a survey on one existing rammed earth house constructed almost 15 years ago. It was extracted soil of the surroundings of the construction site to investigate by laboratory tests the compressive strength of the material as constructed in day one and compared against the existing one. It was observed that the water content plays an important role in the compressive strength. The new earth specimens with similar water content as the existing wall samples, presented five times more compressive strength. Finally, advantages and disadvantages are highlighted about the behaviour and durability of this sustainable material.