Influence of Silicon/Aluminium Ratio on the Strength Properties of Kaolin (Metakaolin) Geopolymer Mortar in Alkaleri, Bauchi State, Nigeria

  • Napoleon Usman Modibbo Adama University of Technology Yola, School of Environmental Sciences, Department of Building, PMB 1076, Yola, Adamawa State, Nigeria
  • Changlia H. Salihu Modibbo Adama University of Technology, Yola, School of Environmental Sciences, Department of Building, Adamawa State, Nigeria
  • Solomon M. S. Department of Building, Faculty of Environmental Science, Nigerian Army University, Biu, Borno State, Nigeria
  • Abeku M. Deri Ministry of Works and Housing Kaduna State, Nigeria
  • F. N. Isa Department of Building, Faculty of Environmental Science, Nigerian Army University, Biu, Borno State, Nigeria
Keywords: Ambient temperature, Kaolin, Geopolymerization, Silicon/Aluminium Ratio, Strength Properties

Abstract

The production of concrete contributes to climate change through the emission of greenhouse gases to the atmosphere which causes global warming. In recent years, geopolymer binders were proposed in an effort to find a sustainable and environmentally friendly alternative to Portland cement concrete. However, geopolymerization were carried out at high temperature and for it to find novel applications within the construction industry, attempts were made to produce structural geopolymer at ambient conditions. In that effect, the study analyzed the influence of local kaolin in producing geopolymer mortar with varied Si/Al ratio at ambient condition. Indigenous kaolin obtained from Alkaleri LGA of Bauchi state and calcined at 700°C for 3 hours was used as the main geopolymer precursor. Physical and chemical properties of the metakaolin were assessed to establish its suitability for geopolymerization. The alkaline activating agents used were Sodium hydroxide of 12M concentration and Sodium silicate to induce the geopolymerization. The geopolymer mortar was prepared with Silicon/Aluminium ratio of 1.6, 2.0, 2.5 and 3.0 having Na2SiO3/NaOH ratio of 0, 1.3, 2.6 and 2.9 respectively. Samples were subsequently cured for 3, 7 and 28 days at ambient condition (average temperature of 26°C and 61± 15% average relative humidity). Compressive strength test was conducted on the geopolymer mortar at appropriate curing age. Experimental results showed that the compressive strengths were in the range of 6.02N/mm2 to 22.35N/mm2 and the strength of the geopolymer mortar increased with increase in the Si/Al ratio, with the maximum compressive strength of 22.35N/mm2 for geopolymer mortar of Si/Al ratio 3.0 attained at 28 days of curing. From the findings, it was concluded that Alkaleri calcined kaolin has shown encouraging potentials for use as an alternative binder for construction purposes.The production of concrete contributes to climate change through the emission of greenhouse gases to the atmosphere which causes global warming. In recent years, geopolymer binders were proposed in an effort to find a sustainable and environmentally friendly alternative to Portland cement concrete. However, geopolymerization were carried out at high temperature and for it to find novel applications within the construction industry, attempts were made to produce structural geopolymer at ambient conditions. In that effect, the study analyzed the influence of local kaolin in producing geopolymer mortar with varied Si/Al ratio at ambient condition. Indigenous kaolin obtained from Alkaleri LGA of Bauchi state and calcined at 700°C for 3 hours was used as the main geopolymer precursor. Physical and chemical properties of the metakaolin were assessed to establish its suitability for geopolymerization. The alkaline activating agents used were Sodium hydroxide of 12M concentration and Sodium silicate to induce the geopolymerization. The geopolymer mortar was prepared with Silicon/Aluminium ratio of 1.6, 2.0, 2.5 and 3.0 having Na2SiO3/NaOH ratio of 0, 1.3, 2.6 and 2.9 respectively. Samples were subsequently cured for 3, 7 and 28 days at ambient condition (average temperature of 26°C and 61± 15% average relative humidity). Compressive strength test was conducted on the geopolymer mortar at appropriate curing age. Experimental results showed that the compressive strengths were in the range of 6.02N/mm2 to 22.35N/mm2 and the strength of the geopolymer mortar increased with increase in the Si/Al ratio, with the maximum compressive strength of 22.35N/mm2 for geopolymer mortar of Si/Al ratio 3.0 attained at 28 days of curing. From the findings, it was concluded that Alkaleri calcined kaolin has shown encouraging potentials for use as an alternative binder for construction purposes.The production of concrete contributes to climate change through the emission of greenhouse gases to the atmosphere which causes global warming. In recent years, geopolymer binders were proposed in an effort to find a sustainable and environmentally friendly alternative to Portland cement concrete. However, geopolymerization were carried out at high temperature and for it to find novel applications within the construction industry, attempts were made to produce structural geopolymer at ambient conditions. In that effect, the study analyzed the influence of local kaolin in producing geopolymer mortar with varied Si/Al ratio at ambient condition. Indigenous kaolin obtained from Alkaleri LGA of Bauchi state and calcined at 700°C for 3 hours was used as the main geopolymer precursor. Physical and chemical properties of the metakaolin were assessed to establish its suitability for geopolymerization. The alkaline activating agents used were Sodium hydroxide of 12M concentration and Sodium silicate to induce the geopolymerization. The geopolymer mortar was prepared with Silicon/Aluminium ratio of 1.6, 2.0, 2.5 and 3.0 having Na2SiO3/NaOH ratio of 0, 1.3, 2.6 and 2.9 respectively. Samples were subsequently cured for 3, 7 and 28 days at ambient condition (average temperature of 26°C and 61± 15% average relative humidity). Compressive strength test was conducted on the geopolymer mortar at appropriate curing age. Experimental results showed that the compressive strengths were in the range of 6.02N/mm2 to 22.35N/mm2 and the strength of the geopolymer mortar increased with increase in the Si/Al ratio, with the maximum compressive strength of 22.35N/mm2 for geopolymer mortar of Si/Al ratio 3.0 attained at 28 days of curing. From the findings, it was concluded that Alkaleri calcined kaolin has shown encouraging potentials for use as an alternative binder for construction purposes.

Published
2020-10-31
How to Cite
Usman, N., Salihu, C. H., M. S., S., Deri, A. M., & Isa, F. N. (2020). Influence of Silicon/Aluminium Ratio on the Strength Properties of Kaolin (Metakaolin) Geopolymer Mortar in Alkaleri, Bauchi State, Nigeria. Journal of Building and Environmental Engineering, 1(1), 23-33. Retrieved from https://journal.scientiaca.org/index.php/jbee/article/view/124
Section
Articles