dc.description.abstract |
The study focused on finding the cheapest construction material besides creating awareness for
society to use available construction materials, it also focused on saving virgin materials. .
Therefore, this research studied sawdust ash as a supplementary cementing material using
mortar with various tests in the fresh, hardened, and microstructure of cement mortar. The
partial replacement of cement with 5%, 10%, 15%, 20%, 25%, 30%, 35%, and 40 % of sawdust ash was executed with 0.55 water-cement ratio and 5%, 10%, 15%, and 20% of saw-dust
ash was executed with 0.485 water-cement ratio at 3
rd
days, 7
th
days, 28
th
days, 56
th
days and
91
st
days curing ages in contrast to the reference (control mix). To meet the objectives, the
study: X-ray fluorescence (XRF) was implemented for the sawdust ash; consistency,
soundness, setting time and flow table were implemented for the fresh cement mortar (cement
paste); compressive strength, ultrasonic pulse velocity, sulphate attack, and water absorption
were implemented for harden cement mortar; Fourier transform infrared spectroscopy was
implemented for microstructure of mortar cubes; and finally, BET was implemented for
physical properties of cement mortar. The results show that sawdust ash saw dust ash of Cordia
Africana (Wanza), Eucalyptus camaldulensis (Bahir-Zaf) and Juniperus procera (Tsed) is a
cementatious material with chemical composition (SiO2 + Al2O3 + Fe2O3) 28.62% of of SDA
and 31.22% of CaO. The fresh properties of sawdust ash blended mortar affected by the saw
dust ash percent in the mix increases; however, 5% of SDA replacement does not show any
significance variation with the control mix. The partial replacement of cement with SDA in the
harden mortar cubes shows an improvement at 5% replacement, though others show the
decreasing in compressive strength, UPV, sulfate attack resistance, and increasing of w ater
absorption than the reference mix. This research takes the attention of the stakeholders in the
construction sector. Because the majority of the people of Ethiopia use wood products for
cooking and other domestic purposes while the ash is practically a waste that is found
abundantly. Therefore, using the sawdust ash as partial replacement cement in the production
of cement mortar positively affects the growing construction industry in the country.
Keywords: SDA, Cement Mortar, Compressive Strength, UPV, Sulphate Attack, Water
Absorption, Microstructure, Water-Cement Ratio |
en_US |