Search

Concrete is the most commonly used building material. Even then, it has a drawback that it hasheavy density. Hence, researches are progressing everywhere to develop a new building material, which has low density, less water absorption as well as economical. And here lies the importance of foamed concrete. Foamed concrete is a type of lightweight concrete in which stable foam is used as the main ingredient. Stable foam is produced from standard foaming agent using a foam generator. The peculiarity of foamed concrete is that no coarse aggregate is used in it. An attempt is made in this research to use palm oil fuel ash as a partial replacement for cement and red gypsum as a partial replacement for manufactured sand. Both of these materials are waste materials and are abundantly available. The concrete made up of this will be more sustainable as well as economical. By adjusting the addition of stable foam, foamed concrete of various densities can be developed. Foamed concrete blocks made up of these materials can be used for load bearing as well as non-load bearing masonry works. It has been observed that the addition of Palm Oil Fuel Ash and Red Earth has improved the properties of foamed concrete.

This work’s goal is to investigate the influence of the type and size of fine aggregate on the characteristics of foamed concrete. Foamed concrete was produced, and its fresh and mechanical characteristics were investigated. It was found that the spread diameter decreased when the foam was added to mixes. With regards to sand grading, when the grading of sand decreased, the diameter of the flow decreased also. Strength improved for fineness sand and enabled the production of uniform and pore distribution, which enhanced the foamed concrete's strength. The increase in compressive strength reflects the other properties of concrete, like tensile strength, that also improved.

The properties of foamed concrete reinforced with carbon fibres and hybrid fibres of carbon with polypropylene fibres has been studied. Various volumetric fractions of carbon fibres (0.5, 1 and 1.5%), hybrid fibres of carbon fibres (CF) with polypropylene fibres (PPF) as (1% CF + 0.5% PPF) & (0.5% CF + 1% PPF), also the mono polypropylene fibres as 1.5% PPF were used to reinforce foamed concrete mix. Fresh and hardened properties of all mixes included flowability, density, absorption, compressive strength, splitting tensile strength, and flexural strengths has been tested. Results showed that inclusion of carbon fibres up to 1% volumetric fraction may increase the compressive strength by about 36% higher than that of control mix. Whereas, the use of 1.5% carbon fibres exhibit significant increase in splitting and flexural tensile strengths by about 47 and 114%, respectively, compared to the reference mix. On the other hand, the hybridization of 1% CF + 0.5% PPF increased the splitting tensile strength and flexural strengths by 53% and 114%, respectively, compared with plain foamed concrete mix.