The present study assesses the performances of compressed earth bricks (CEB) stabilized with calcined-clay-based geopolymer. The geopolymer binder was synthesized from local kaolin-rich clay calcined at 700 °C to transform it into amorphous and reactive metakaolin (MK). The lateritic earthen material, which has a grain size of 0/5 mm, was stabilized with 0, 5, 10, 15 % geopolymer binder; and 8% Portland cement for control, with respect to the mass of dry earthen material. The alkali solution of sodium hydroxide (NaoH, 12 M) was added to the dry mixtures for the activation of the MK and production of wet mixtures, which were manually and statically compressed (~35 bar) in mould (295 x 140 x 95 mm3 ) of Terstaram machine to produce the CEB. Stabilized CEBs were cured for 14 days (7 days at room temperature 30 ± 5 °C and 7 days in an oven at 60 °C), while those stabilized with cement were cured at room temperature 30 ± 5 °C for 28 days. The CEBs were dried and characterized for their physico-mechanical properties. The results showed a clear improvement in the performance of CEB stabilized with up to 20% geopolymer. The water accessible porosity was 27.4% for CEBs stabilized with 15% geopolymer, against 26% for CEBs stabilized with 8% cement. The dry and wet compressive strength were 9.8, and 4.8 MPa for CEB stabilized with 15% geopolymer, against 6.6 and 4.7 MPa for CEB stabilized with 8% cement. All indicators show that CEB stabilized with geopolymer can be used in modern construction.

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