Furthermore, the soil-based ancient

Furthermore, the soil-based ancient buildings have characteristics
of coolness in the summer and warmth in the winter for the
existing of natural micro-pore structures in mud walls. Inspired
by this discovery, several researchers have introduced soil into
lightweight concrete [6,7]. Goual et al. studied clayey cellular
concrete and found that the compressive strength and thermal
conductivity ranged from 0.95–3.85 MPa and 0.201–0.281 W/m K
for densities of 843–1038 kg/m3, respectively [7]. Porosity identification
revealed the existence of two distinct pores classes: inherent
micropores in the clay and macropores or gaseous cells,
resulting from the addition of aluminium powder at the time of
mixing. On account of the only moderate strength requirement
for foamed concrete, soil can be used as eco-friendly and cheap
filler for creating novel foamed concrete some excellent properties.