Enhancing Hempcrete and Hemp Concrete Properties through Surface Treatment and Additives

The research presented results on improving the properties of hempcrete and hemp concrete by pretreating the hemp surface using aluminum sulfate with 3 other additives including plasticizers, natural rubber latex, and polymer. The aim of the research was to investigate the changes in the compressive strength of the blocks. Hempcrete samples were produced with a ratio by weight of hemp to lime of 1:12 and a water content of 34.62% by weight. Hemp concrete samples had a ratio of hemp:hydraulic cement:soil of 1:4:8 and a water content of 34.62% by weight. Both samples were formed using a 7.5 x 30 x 10 cm steel mold. Results from the compressive strength test found that the strength for both hempcrete and hemp concrete improved using 10% by weight aluminum sulfate together with polymer had the highest increase in strength in comparison to the other cases in this study. The compressive strength obtained was 1.21 MPa for hempcrete and 2.83 MPa for hemp concrete, resulting in an increase of 55.13% and 194.79%, respectively. These results showed that this method for improving the properties of hemp concrete made its compressive strength higher than the standard for nonloadbearing concrete masonry as required by construction standards.