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- Majeed, Samadar S., et al.
(författare)
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Development of ultra-lightweight foamed concrete modified with silicon dioxide (SiO2) nanoparticles: Appraisal of transport, mechanical, thermal, and microstructural properties
- 2024
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Ingår i: Journal of Materials Research and Technology. - : Elsevier. - 2238-7854 .- 2214-0697. ; 30, s. 3308-3327
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Tidskriftsartikel (refereegranskat)abstract
- Over the last few decades, researchers have devoted significant consideration to the use of nanoscale elements in concrete. Silicon dioxide nanoparticles (SDNs) have been a popular subject of study among the several types of nanoparticles. This article describes the findings of a laboratory investigation that examined the properties of ultra-lightweight foamed concrete (ULFC) including different proportions of SDNs. Wide range of the properties was evaluated specifically the slump flow, density, consistency, flexural strength, modulus of elasticity, compressive strength, split tensile strength, thermal properties, porosity, water absorption, sorptivity, intrinsic air permeability, and chloride diffusion. Additionally, the scanning electron microscopy (SEM) and pore distributions analyses of different mixes were done. Results confirmed a noticeable increase in the mechanical properties of ULFC, with respective improvements in the 28-day compressive, split tensile, and flexural strengths of up to 70.49%, 76.19%, and 51.51%, respectively, at 1.5% of the SDNs inclusion. However, further increases in the SDNs percentage did not result in remarkable enhancements. As the SDN percentage increased from 1.5% to 2.5%, the ULFC’s sorptivity, porosity, water absorption, intrinsic air permeability, and chloride diffusion showed substantial improvements. When compared to the control sample, ULFC with SDNs demonstrated higher thermal conductivity values. The reason for this occurrence was determined to be the smaller pore size observed in the ULFC specimens containing SDNs. A great adjustment in the distribution of pore diameters was witnessed in the ULFC mixes when the percentages of SDNs were adjusted. The ULFC specimens, which included SDNs at the percentages of 0.5%, 1.0%, and 1.5%, indicated a reduction in the total number of large voids measuring 500 nm or more, compared to the control ULFC specimen. The findings of this study highlight the potential benefits of incorporating SDNs into ULFC, which may improve its overall properties.
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- Mydin, Md Azree Othuman, et al.
(författare)
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Enhanced fresh and hardened properties of foamed concrete modified with nano-silica
- 2024
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Ingår i: Heliyon. - : Elsevier. - 2405-8440. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- Nowadays, the application of nanotechnology has gained increased attention in the concrete technology field. Several applications of concrete require light weight; one such concrete used is foamed concrete (FC), which has more voids in the microstructure. In this study, nano-silica (NS) was utilized, which exhibits a pozzolanic nature, and it reacts with other pozzolanic compositions (like lime, alumina, etc.) to form hydrated compounds in concrete. Apart from these hydrated compounds, NS acts as a filler material and enhances properties of concrete such as the fresh and hardened properties. This research examines the fresh, hardened, and microstructural properties of FC blended with NS. The ratio of binder and filler used in this research is 1:1.5, with a water-to-binder ratio of 0.45 and a density of 880 kg/m3. A total of six different weight fractions of NS were added to FC mixes, namely 0%, 1%, 2%, 3%, 4%, and 5%. Properties assessed for FC blended with NS were the slump, bulk density, strength parameters (flexural, splitting tensile, and compressive strengths), morphological analysis, water absorption, and porosity. It was concluded from this study that the optimum NS utilized to improve the properties was 3%. Apart from this, the relationship between the mechanical properties and NS dosages was developed. The correlations between the compressive strength and other properties were analyzed, and relationships were developed based on the best statistical approach. This study helps academicians, researchers, and industrialists enhance the properties of FC blended with NS and their relationships to predict concrete properties from other properties.
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- Mydin, Md Azree Othuman, et al.
(författare)
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Study on fresh and hardened state properties of eco-friendly foamed concrete incorporating waste soda-lime glass
- 2024
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Ingår i: Scientific Reports. - : Springer. - 2045-2322. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Improper waste management is causing global environmental problems. Waste glass may have adverse impacts on the ecosystem. While a substantial amount of soda-lime glass bottle (SGB) undergoes recycling to create new glass items, a significant volume still ends up in landfills. Therefore, the aim of this study was to explore the potential use of SGB in foamed concrete (FC) production as an aggregate replacement. SGB was substituted for sand in different weight fractions, ranging from 5 to 50%. The fresh state, mechanical, thermal, pore structure, and transport properties were examined. The findings showed a significant enhancement in the FC’s mechanical properties when SGB replaced 20% of sand. The compressive, flexural, and splitting tensile strengths exhibited a rise of up to 17.7, 39.4, and 43.8%, respectively. The findings also demonstrated that the addition of SGB improved the thermal conductivity, sorptivity, water absorption, and porosity. The scanning electron microscopy analysis indicated that the inclusion of 20% SGB caused a substantial decrease in void diameter and enhanced its uniformity. A comparison was made between the experimental data and predictions of the mechanical properties using various models of international standards, such as IS 456, ACI 318, NZS-3101, EC-02, AS 3600, and CEB-FIB, along with several references in the literature. The findings implied a strong correlation between the strength properties. The outcomes of this research offer valuable insights into both the possible advantages and constraints of using SGB in FC. Furthermore, this extensive laboratory investigation may serve as a guideline for future study and aid in the advancement of greener and more environmentally friendly FC alternatives.
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4. |
- Mydin, Md Azree Othuman, et al.
(författare)
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Study on freshness, morphology, strength, and durability properties of foamed concrete reinforced with agave fiber
- 2024
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Ingår i: Journal of Engineered Fibers and Fabrics. - : Sage. - 1558-9250. ; 19, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- Currently, foamed concrete (FC) is widely employed in building construction and civil engineering works, and by using abundant natural fibers in FC, significant environmental benefits can be obtained. The durability properties of the essential materials acting independently could well be enhanced if the appropriate proportion of natural fiber-strengthened FC were used in the correct volume. This study aimed to develop new composite materials composed of FC and agave fiber (AF). The objective was to ascertain the optimal proportion of AF to be added to FC to increase its durability performance. A low-density FC of 950 kg/m3 was fabricated utilizing varying percentages of AF, namely 0% (control), 1.5%, 3.0%, 4.5%, 6.0%, and 7.5%. The evaluated properties were the shrinkage, workability, density, water absorption, ultrasonic pulse velocity, porosity, compressive strength, and elastic modulus. Using AFs in FC, the optimal shrinkage and ultrasonic pulse velocity were observed. When the weight fractions of AF were increased from 1% to 4.5% in the mixtures, the porosity, workability, and water absorption of FC were significantly reduced. In addition, FC showed a slight increase in the dry density with the rise in the AF’s weight fraction and the increase in the curing age from day-7 to day-56. This research delivers noteworthy data on the durability properties of FC-AF composites, allowing future researchers to study other properties like the structural performance, strength properties, and thermal conductivity of FC-AF composites.
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