Behavior Of Low-Carbon Rice Husk Ash In Cement Mortar Under Compressive Loading

This study explores the impact of low carbon Rice Husk Ash (RHA) on the rheological and mechanical properties of mortar. RHA, sourced from Nigeria, underwent chemical analysis to ascertain its pozzolanic activity index. Rheological tests conducted on the mortar included standard consistency, initial and final setting times, as well as fresh density of mortar. While mechanical properties such as compressive, tensile, and flexural strength were assessed. Ordinary Portland Cement (OPC) was partially substituted with RHA at varying intervals with 0% RHA serving as the control. Compressive strength was measured after 7, 14, and 28 days of water curing, while tensile and flexural strength were evaluated at the 28th day. The water-to-binder ratio was fixed at 4.85, and binder-to-fine aggregate ratios of 1:2.36 and 1:2.76 were employed. RHA was classified as Class N, indicating high pozzolanic capacity. Results revealed increased consistency, initial and final setting times and a decreased density with RHA addition. The peak compressive strength was observed at 10% RHA, reaching 8.759 and 10.252 MPa for mix ratios 1:2.75 and 1:2.36, respectively. Moreover, at 10% RHA, flexural and tensile strength for mix ratio 1:2.36 exceeded those of plain mortar by 22.5% and 9.6%, respectively. In conclusion, the study highlights the significant role of RHA as a pozzolanic material in enhancing cementitious reactions in mortar systems, though the influence of RHA particle size was not considered.

Behavior Of Low-Carbon Rice Husk Ash In Cement Mortar Under Compressive Loading Keywords:

Pozzolans , Compressive strength , tensile strength , Mortar , Flowability