The high content of clay fraction is very annoying to the homogenization step of the soil-cement mixture. This
may affect the cement hydration process (Rodrigues, 2012). The waste sample presented high plasticity (Atterberg
plastic index = 25.4 %), and is well correlated with the particle size distribution data. In addition, the plasticity
index value suggests that the water treatment plant waste could be used to manufacture soil-cement bricks, since it
is added in small amounts.