Shekhawat, P; Sharma, G and Singh, R M (2020) Durability analysis of eggshell powder–flyash geopolymer composite subjected to wetting–drying cycles. Journal of Engineering, Design and Technology, 18(6), pp. 2043-2060. ISSN 1726-0531
Abstract
Purpose: The purpose of this study is to investigate the effect of various heat conditions on the durability of eggshell powder (ESP)–flyash (FA) geopolymer subjected to wetting–drying cycles. Design/methodology/approach: In this study, two waste materials, ESP and FA, which are destined for landfills, were used as precursors to produce geopolymers in a sustainable manner. The mixture of Na2SiO3 and NaOH was used as a liquid alkaline activator in geopolymerization. The ESP and FA content were varied as 30, 50 and 70% and Na2SiO3/NaOH ratios were varied as 0.5, 1 and 2. Geopolymer samples were cured at three heat conditions: 25°C (ambient temperature), 50°C and 80°C for seven days prior to durability tests. Findings: The results of this study revealed that the strength loss of the geopolymer decreases with an increase in curing temperature up to 50°C and then increases for higher temperature up to 80°C. Further, the strength loss of the geopolymer decreases with an increase in FA replacement and Na2SiO3/NaOH ratio. Geopolymer composites exhibited early strength development because of the inclusion of calcium-rich ESP. The weight loss of the ESP–FA geopolymer follows a similar pattern of strength loss. Geopolymer samples previously cured at optimum heat condition of 50°C for seven days exhibited higher durability. Originality/value: The inclusion of calcium-rich ESP in FA-based geopolymer is novel research. As ESP–FA geopolymer composites show higher mechanical strength and higher durability compared to Indian standards, the potential use of this geopolymer can be in road subbases/subgrades.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | durability; eggshell powder; flyash; geopolymer; pavement |
| Index terms: | ambient temperature, methodology, curing, landfill, replacement, mechanical strength, composite, waste material, durability |
| Subjects: | environmental science, material degradation and durability, materials science, waste management, environmental engineering, concrete and cementitious materials, research methods, material properties and characteristics |
| Topics: | Research Practice, Engineering Principles, Construction Materials, Sustainability |
| Descriptive scope: | 3 PCT |
N.B. Descriptive scope is a count of how many of the five facets of empirical research are indicated by the words used in title, abstract and keywords. It is not intended as a judgement on the research; merely a count of the kind of word we would expect to indicate Phenomenon, Concepts, Theoretical framing, Empirical techniques, Analytical techniques. If all five are present, then a code of “5 PCTEA” will indicate this. If you feel the coding for this record is questionable, we welcome discussion around the terms we matched or the way we categorized them. The facet you would expect may not be coded, or a facet may be coded inappropriately. This can also bear on a larger question, of which facets should be treated as defining in construction management research. Please get in touch, and we will look at it. More details here