Mechanical behaviour of hypercompacted earth for building construction

This paper investigates the mechanical behaviour of a hypercompacted unstabilized earth material manufactured by compressing a moist soil to very high pressures up to 100 MPa. The hypercompaction procedure increases material density, which in turn improves mechanical characteristics. Samples were manufactured at the scale of both small cylinders and masonry bricks. The effect of ambient humidity on the mechanical characteristics of the material was investigated at the scale of cylindrical samples, showing that both strength and stiffness are sensitive to environmental conditions and tend to increase as ambient humidity reduces. The strength of the bricks was instead investigated under laboratory ambient conditions by using different experimental configurations to assess the influence of sample slenderness and friction confinement. Additional tests were also performed to evaluate the influence of mortar joints and compaction-induced anisotropy. Overall, the hypercompacted earth material exhibits mechanical characteristics that are comparable with those of traditional building materials, such as fired bricks, concrete blocks or stabilized compressed earth.