Rammed Earth with Brick Waste and Influence of Moulding Water Content and Lime

Excavation soil from a construction site in Zealand, Denmark, was evaluated as raw material for rammed earth (RE). Since the soil fell outside the recommended area for the grain size distribution, fractions of brick waste (BW) were added as aggregates to the raw soil. The addition of binders consisting of lime and brick powder (BP) was also investigated as well as the influence of several moulding water contents for each test series. RE specimens were evaluated based on unconfined compressive strength (UCS), UC stiffness, drying shrinkage deformations, bulk density, and erosion properties. Results show that the UCS decreased with increasing BW, although 25% BW resulted in almost the same UCS and UC stiffness as the reference. The drying shrinkage was slightly reduced with the addition of BW. However, when immersed in water, all specimens without binder completely eroded. The two specimens with binder reached lower UCS than those without, but the advantage of the lime stabilization was seen in the water immersion test, where no erosion happened. The optimum water content (OWC) increased, and bulk density decreased with both BW and binder.