Stabilization effects on the thermal conductivity and sorption behavior of earth bricks

Future of clay-based construction materials – A review

“…Additionally, the CSBs under water curing exhibited higher strength than that under air curing. This was attributed to the fact that more hydration products from the reaction between the cement and soil could be formed in the Saidi et al [39] evaluated the effect of cement and lime content on the thermal conductivity of stabilised earth blocks (SEB). The results indicated that with increased stabiliser content, the thermal conductivity increased, which in turn resulted in decreasing the thermal insulation.…”

“…According to the reviewed studies and amongst the variety of stabilizers utilised, cement and lime have been the most popular stabilizers in the production of stabilised clay-based construction materials. Cement and/or lime were used either alone [37][38][39][42][43][44], in combination with each other [35,36] or in combination with other stabilisers such as GGBS or PFA [45][46][47]. However, two of the reviewed studies were used different stabilisers such as calcium carbide residue with rice husk ash [40] and magnesium oxide rich kiln dust [41].…”

“…For example, the cement dosage was ranging between 3% and 12% [37][38][39]43] and only one paper [42] have showed the usage of 20% cement as stabiliser. The dosage of lime as stabiliser was similar to that of the cement (ranging between 2% and 12%).…”

“…The reviewed studies indicated that the production of C-S-H and C-A-S-H gel phases increased with increasing the amounts of stabiliser in the mixture [36,37,39,40,45]. This was due to the chemical reaction occurring between the CaO from the cement, lime and other stabilisers and amorphous silica provided by clay together with the high alkalinity environment of cement or lime [37,39,45,46]. These gels tend to fill pores and grow into capillary spaces, resulting in a more impermeable, dense and higher-strength structure [48,49].…”

“…Since clay-based brick and blocks are recognised as materials which contribute towards the thermal insulation of buildings and consequently increase indoor comfort, some of the research projects [39,43,45,51,55] investigated this property. The results indicated that the thermal isolation of the clay-based unities have been reduced slightly with increasing the stabiliser content [39,43,45], however, the use of alkaline activators and especially in the presence of FA improved the thermal isolation of the clay-based unites [51,55].…”