The purpose of this work is to study the influence of Rice Husk Ash (RHA) on the mechanical strength of mortars. For this purpose, ash was produced by calcining rice husk at 680°C for 5 hours to produce reacti...The purpose of this work is to study the influence of Rice Husk Ash (RHA) on the mechanical strength of mortars. For this purpose, ash was produced by calcining rice husk at 680°C for 5 hours to produce reactive pozzolan. The chemical and mineralogical composition studied by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and X-Ray Diffraction (XRD) showed that this ash is rich in amorphous silica. The ash presents a good pozzolanic activity with a lime fixation rate of 100% after only 7 days of treatment. The addition of RHA to cement contributes to the formation of calcium silicate hydrate (CSH) and calcium aluminate hydrate of C3ASH6 type. The presence of RHA in the mortars improves their mechanical strength. This improvement is due to the filler effect of RHA and to formation of the CSH resulting from the pozzolanic reactivity between the amorphous silica of the RHA and the portlandite released by hydration of the cement.展开更多
The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used ...The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used for the study. Ordinary Portland cement （OPC） was partially replaced with rice husk ash at 20% by weight of binder. The water to binder ratio （W/B） of the mortar was maintained at 110%±5% with flow table test. Specific gravity, fineness, chemical properties, compressive strength, and porosity test of mortars were determined. The differences in chemical composition of the rice husk ashes with different finenesses from the same batch are small. The use of RHA3 produces the mortars with good strength and low porosity. The strength of the mortar improves with partial replacement of RHA3 in comparison with normal coarse rice husk ash. The use of RHA3 results in a strong and dense mortar, which is due to the better dispersion and filling effect, as well as an increase in the pozzolanic reaction.展开更多
文摘The purpose of this work is to study the influence of Rice Husk Ash (RHA) on the mechanical strength of mortars. For this purpose, ash was produced by calcining rice husk at 680°C for 5 hours to produce reactive pozzolan. The chemical and mineralogical composition studied by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and X-Ray Diffraction (XRD) showed that this ash is rich in amorphous silica. The ash presents a good pozzolanic activity with a lime fixation rate of 100% after only 7 days of treatment. The addition of RHA to cement contributes to the formation of calcium silicate hydrate (CSH) and calcium aluminate hydrate of C3ASH6 type. The presence of RHA in the mortars improves their mechanical strength. This improvement is due to the filler effect of RHA and to formation of the CSH resulting from the pozzolanic reactivity between the amorphous silica of the RHA and the portlandite released by hydration of the cement.
基金the Commission on Higher Education (MUA) of Thailandthe Sustainable Infrastructure Research and Development Center of Khon Kaen University (SIRDC)Department of Civil Engineering of Rajamangala University of Technology Phra Nakhon (RMUTP)
文摘The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used for the study. Ordinary Portland cement （OPC） was partially replaced with rice husk ash at 20% by weight of binder. The water to binder ratio （W/B） of the mortar was maintained at 110%±5% with flow table test. Specific gravity, fineness, chemical properties, compressive strength, and porosity test of mortars were determined. The differences in chemical composition of the rice husk ashes with different finenesses from the same batch are small. The use of RHA3 produces the mortars with good strength and low porosity. The strength of the mortar improves with partial replacement of RHA3 in comparison with normal coarse rice husk ash. The use of RHA3 results in a strong and dense mortar, which is due to the better dispersion and filling effect, as well as an increase in the pozzolanic reaction.
