Effect of Partial Replacement of Ordinary Portland Cement (OPC) with Ghanaian Rice Husk Ash (RHA) on the Compressive Strength of Concrete  

作　　者：Derrick Nii-Laryea Botchway Russell Owusu Afrifa Charles Yeboah Henaku Derrick Nii-Laryea Botchway;Russell Owusu Afrifa;Charles Yeboah Henaku(Civil Engineering Department, Takoradi Technical University, Takoradi, Ghana;Civil Engineering Department, Kwame Nkrumah University of Science & Technology, Kumasi, Ghana)

机构地区：[1]Civil Engineering Department, Takoradi Technical University, Takoradi, Ghana [2]Civil Engineering Department, Kwame Nkrumah University of Science & Technology, Kumasi, Ghana

出　　处：《Open Journal of Civil Engineering》2020年第4期353-363,共11页土木工程期刊（英文）

摘　　要：The cost of cement has made concrete production expensive such that the housing deficit in developing countries is on the rise despite all the efforts by governments and other stakeholders to produce affordable housing units for the populace. Ashes of agricultural products such as rice husk, known as mineral admixtures may have pozzolanic characteristics which would be more beneficial to the housing industry in terms of strength gain and economy than being pollutants to the environment. Rice Husk Ash (RHA), because of its finely divided form and very high silica content and amorphousness, proved to be useful for strength gain of Rice Husk Ash Concrete (RHAC). Rice husk ash was manufactured by uncontrolled burning, ground, sieved and replaced with cement at 0%, 5%, 10%, 15%, 20% and 25% in mass for the mixes C20, C25, C30 and C35 where their compressive strengths were verified at 3, 7, 14, 21, 28, 56, 90 and 180 days. The X-ray diffraction pattern list indicated amorphous as well as diffused peak of about 8000 counts of SiO</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;"> representing crystalline structures identified as cristobalite. A physical examination of the RHA showed very fine appearance, grey color and specific gravity of 2.06. The chemical analysis also revealed the existence of oxide content to be 55.8% representing 0.78% of Fe</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;">O</span>_{<span style="font-family:Verdana;">3</span>}<span style="font-family:Verdana;">, 54% of SiO</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;"> and 1.06% of Al</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;">O</span>_{<span style="font-family:Verdana;">3</span>}<span style="font-family:Verdana;"> representing 20.23% lower than the minimum value of 70% required for pozzolans. Generally, the compressive strength values decreaseThe cost of cement has made concrete production expensive such that the housing deficit in developing countries is on the rise despite all the efforts by governments and other stakeholders to produce affordable housing units for the populace. Ashes of agricultural products such as rice husk, known as mineral admixtures may have pozzolanic characteristics which would be more beneficial to the housing industry in terms of strength gain and economy than being pollutants to the environment. Rice Husk Ash (RHA), because of its finely divided form and very high silica content and amorphousness, proved to be useful for strength gain of Rice Husk Ash Concrete (RHAC). Rice husk ash was manufactured by uncontrolled burning, ground, sieved and replaced with cement at 0%, 5%, 10%, 15%, 20% and 25% in mass for the mixes C20, C25, C30 and C35 where their compressive strengths were verified at 3, 7, 14, 21, 28, 56, 90 and 180 days. The X-ray diffraction pattern list indicated amorphous as well as diffused peak of about 8000 counts of SiO</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;"> representing crystalline structures identified as cristobalite. A physical examination of the RHA showed very fine appearance, grey color and specific gravity of 2.06. The chemical analysis also revealed the existence of oxide content to be 55.8% representing 0.78% of Fe</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;">O</span>_{<span style="font-family:Verdana;">3</span>}<span style="font-family:Verdana;">, 54% of SiO</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;"> and 1.06% of Al</span>_{<span style="font-family:Verdana;">2</span>}<span style="font-family:Verdana;">O</span>_{<span style="font-family:Verdana;">3</span>}<span style="font-family:Verdana;"> representing 20.23% lower than the minimum value of 70% required for pozzolans. Generally, the compressive strength values decrease

关 键 词：Rice Husk Ash Agricultural Waste Mineral Admixture Pozzolanic Activity Compressive Strength 

分 类 号：TB3[一般工业技术—材料科学与工程]