Abstract:
The concept of using cleaner production technologies has become prominent in the present context
for achieving sustainability in construction. It has been proven that by incorporating agricultural
waste as cement replacement, mechanical and durability properties of the resulting mortar have
been enhanced. A comparative study on the mechanical, thermal, and environmental performance
of a newly developed lightweight mortar containing agro-wastes namely Bagasse Ash (BA) and
Rice Husk Ash (RHA) were investigated. Ordinary Portland cement was partially replaced by BA
at dosages of 0%, 5%, 15%, 20%, and 30% and RHA at dosages of 0%, 5%, and 15% by weight.
A detailed investigation was carried out to determine the best suited material mix which can
achieve very good material properties.
Results indicated that the mixtures with the replacement percentages up to 30% by both BA and
RHA for cement had compressive strength confined to the standard recommended range (~5.2
MPa) while maintaining the adequate water absorption and acid alkaline resistance. This indicates
that BA can be used to replace the cement up to 30% and BA and RHA of each 15% of cement
replacements also can be used to manufacture the mortar for wall plaster and addition of 30% BA
as a partial replacement for cement improved the thermal performance by causing a decrease in
the thermal conductivity about 33%. However, the combination of BA and RHA (15% each)
decreased the thermal conductivity up to 31% compared to the conventional mortar and results
indicated that acid resistance also increased with the increase the percentage of BA and RHA,
Further, the assessment of environmental impact reveals a noticeable reduction in embodied
GHGE with the increasing replacement of BA and RHA in mortar. When the cement in
conventional mortar was substituted with 30% BA and, 15% BA and 15% RHA, both cases
reduced the CO2 emissions by about 28% than the control mix. The cost of control for both mortar
containing 30% BA and mortar containing 15% BA and 15% RHA production is 16.6% of
conventional mortar mix. However, the energy to produce BA mortar is less than BA and RHA
mortar. Thus, BA falls more under the prospective of energy effective, cost-effective, and
environmentally friendly construction materials.
Citation:
Srikanth, G. & Gamage, J.C.P.H. (2021). Development of a plastering mortar using waste bagasse and rice husk ashes with sound mechanical and thermal properties [Abstract]. In P. Hettiarachchi (Ed.), Proceedings of Civil Engineering Research Symposium 2021 (p. 18). Department of Civil Engineering, University of Moratuwa.