Due to their good performance and environmental friendliness, fly ash-based construction materials have great potential as alternatives to ordinary Portland cement. To realize sustainable development and beneficial use of fly ash in the construction industry, this paper presents a comprehensive review of relevant literature to evaluate the properties and performance of fly ash, with a particular focus on recent advances in characterization, compositional understanding, hydration mechanism, activation approaches, durability and sustainability of fly ash as a construction material. Several key aspects governing the performance of fly ash, including chemical composition, activator type and hydrates evolution in concrete, are highlighted. Finally, the important needs, pertinent to the optimal and broad utilization of fly ash as an integral part of sustainable construction materials, are identified for further research and development, where large-scale application studies, further classification of fly ash, advanced characterization tools and technology transfer to biomass fly ash are recommended.

Characteristics and applications of fly ash as a sustainable construction material: A state-of-the-art review

Structural and material performance of geopolymer concrete: A review

Use of geopolymer concrete for a cleaner and sustainable environment – A review of mechanical properties and microstructure

Green concrete: Prospects and challenges

Properties of fresh and hardened fly ash/slag based geopolymer concrete: A review

Durability of fly ash based geopolymer concrete in the presence of silica fume

Water Resource Management: Geodata Analysis Through Google Earth Engine for Water Resources Management and Spatial Planning

This paper is an attempt to present a COVID-19 prediction model for India. Lockdown plays an important role in the arrest of community spread of the disease. This was evident from the study of other countries such as Russia, Belgium and Germany, where peak cases were recorded within a month of the imposition of lockdown, that it showed an immediate positive effect. However, in India, even after 65 days of lockdown, there is no decrease in the number of daily new cases reported. There were many models prepared for India and almost all of them were proven wrong by the increase in the number of cases. The model in this paper is prepared using the COVID-19 trend in other countries, population density and the pandemic bell curve. Based on the available data until 24th May 2020, two scenarios have been presented. In one, the peak shall be obtained when the number of daily new cases per million reaches 190 and in the second when the daily new cases per million reach 724. One model predicts the number of cases to reach 1 million by mid-July 2020. The other model predicts the number of cases to peak by mid-July with the total cases reaching 20 million. The predicted cases were compared with the actual cases recorded for the period 25th May to 11th June 2020. It was observed that the actual values matched quite reasonably with the predicted values.

https://www.preprints.org/manuscript/202006.0214/v1/download

Satya Prakash

Papers

Durability of fly ash based geopolymer concrete in the presence of silica fume

Water Resource Management: Geodata Analysis Through Google Earth Engine for Water Resources Management and Spatial Planning

COVID-19 India Prediction Model Based on the Trend from Other Countries