Characteristics of geopolymer stabilised compressed earth bricks

The geopolymer based binders have low embodied carbon when compared to the Portland cement. The paper focuses on the experimental studies on geopolymer stabilised compressed earth bricks (GCEB's) without using OPC or high temperature firing. Geopolymer binder composing of aluminosilicate materials (fly ash and ground slag) and an activator was used to stabilise the reconstituted soil in manufacturing the GCEB's. The GCEB's showed wet compressive strength more than 20 MPa and wet to dry strength ratio was 0.5. The water absorption and durability characteristics of the bricks were well within the acceptable limits for the satisfactory performance of the masonry units. The leaching of salts was seen in the GCEB's. The compressive strength was not affected due to leaching. The leachate contains mainly sodium carbonate. The findings indicate that GCEB's exhibit lower levels of embodied carbon (EC) and embodied energy (EE) than the values for conventional materials like burnt clay bricks and concrete blocks.