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Environmental concerns and the desire for improved performance in building construction have led to a great deal of attention being paid to developing sustainable construction materials. The engineering characteristics of natural fibre-reinforced one-part geopolymer concrete (NFROPGC), a novel material that combines strong mechanical qualities and offers significant environmental advantages, are examined in this work. Activated by a dry alkali source (Sodium meta–Silicate Anhydrous), one-part geopolymer concrete is more sustainable and easier to use than two-part geopolymer concrete. Fibres from kenaf, coconut, and oil palm measuring 25 mm and containing 0 %, 0.75 %, and 1 % were utilised. The chosen fibres were treated with an alkaline solution of 5 % concentration to enhance their performance. The engineering properties of natural fibre-reinforced one-part geopolymer concrete were measured by determining its workability, compressive, flexural, split tensile, impact resistance strengths, MOE, Poisson's ratio, and water absorption. Also, its morphology was studied under the scanning electron microscope. The flexural, splitting tensile strengths and MOE were improved by including 0.75 % natural fibre in one-part geopolymer concrete. Kenaf, coconut, and oil palm fibre-reinforced one-part geopolymer concrete showed increased flexural strengths from 4.93 MPa to 7.87 MPa, 4.11 MPa to 6.04 MPa, and 4.02 MPa to 5.85 MPa, respectively, while splitting tensile strengths of kenaf, coconut, and oil palm fibre-reinforced one-part geopolymer concrete increased from 3.3 MPa to 4.95 MPa, 3.25 MPa to 4.37 MPa, 2.95 MPa to 3.79 MPa, respectively and the MOE of kenaf, coconut, and oil palm fibre-reinforced one-part geopolymer concrete increased from 37.77 GPa to 44.04 GPa, 37.77 GPa to 42.79 GPa, and 37.77 GPa to 39.61 GPa, respectively. The optimum impact resistance strengths of the reinforced geopolymer concrete for kenaf fibre, coconut fibre, and oil palm fibre were obtained at 1 % fibre content with increments of 122.11 %, 98.33 %, and 88.33 %, respectively. However, fibre-reinforced one-part geopolymer concrete's compressive strength and workability reduced slightly as fibre content rose. The SEM results demonstrate how well fibres fill voids and bridge cracks in one-part geopolymer concrete. Future studies will focus on long-term performance evaluations and scaling up for industrial buildings. • We treated the three selected natural fibres with an alkaline solution to remove dirt and lignin. We carried out SEM analysis on both treated and untreated natural fibres. The morphologies show a rough and smooth surface for treated and untreated fibres, respectively. Also, all the treated fibres had a clean surface. The volumes of fibres used were 0 %, 0.75 %, and 1 % at length of 25 mm. • We designed the constituents of natural fibre-reinforced one-part geopolymer concrete using the innovative Design of Experiment (DOE) method of conventional concrete design. This method, chosen due to the lack of a standard design method, offers a fresh perspective and unique approach to our research. Our target was 40 MPa after 28 days of curing. • We tested the samples of the prepared natural fibre-reinforced one-part geopolymer concrete for compressive, flexural, and split tensile strengths, impact resistance, MOE, Poisson ratio, UPV, and density. We carried out SEM analysis on natural fibre-reinforced one-part geopolymer concrete samples. • We developed models that show the relationship between the engineering properties of natural fibre-reinforced one-part geopolymer concrete. • Adding natural fibre to one-part geopolymer concrete samples improves flexural strength, split tensile strength, impact resistance strength, and MOE. [ABSTRACT FROM AUTHOR]

In the last 3 decades, the attention in consuming substitute materials such as solid wastes in construction has grown continuously. An extensive amount of waste ceramic is being generated all around the world. These wastes are mostly sent to the landfill without considering recycling option. Such waste ceramic in the powder and fine particle forms has good potential in the infrastructure industry. In this study, the strength and durability properties of a mortar comprising ceramic waste powder as supplementary cementing material and ceramic particles were investigated. Properties studied include workability, compressive and tensile strengths, chloride and sulfate resistance. The effect of waste ceramic was also assessed by using scanning electron microscopy and X-ray diffraction analysis. It was observed that the utilization of waste ceramic in both forms of binder and fine aggregate significantly improved the compressive and splitting tensile strengths and higher resistance against chloride and sulfate attacks. The microstructure of the mortar was further enhanced by replacing ceramic waste powder and fine aggregates. It, therefore, caused in the higher crystalline formation and reduction in porosity and cracks in addition to eliminating the spalling behavior of mortar specimens exposed to chloride and sulfate attacks. [ABSTRACT FROM AUTHOR]

• Ceramic waste was used in the production of sustainable mortar. • Mortar with ceramic waste exhibited better compressive strength. • Ceramic waste notably improved mortar resistance against aggressive environments. • The utilisation of ceramic waste in mortar has both technical and environmental benefits. Different types of waste materials generated from various industries require proper and sufficient management to assure a clean environment. The application of solid waste in sustainable construction has attracted much attention due to its potential properties, decreased cost and saving land space that would otherwise be used for landfill purposes. In this study, the long-term performance of mortar comprising ceramic waste powder as supplementary cementing material and ceramic particles as fine aggregates, which were exposed to chloride and sulphate attack, was investigated. The effect of the ceramic waste was also assessed using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis. Results of this study indicated that the utilisation of ceramic waste in both forms of binder and fine aggregates significantly improved the long-term compressive strength of the mortar and provided higher resistance against aggressive environments. The positive interaction amongst the ceramic waste powder and fine aggregates enabled higher crystalline formation, and therefore, reduction in porosity and cracks. In addition, it also prevented the mortar spalling from being exposed to chloride and sulphate attacks. Based on the results, it was concluded that the utilisation of ceramic waste in the production of sustainable mortar that is exposed to aggressive environments is technically and environmentally feasible. [ABSTRACT FROM AUTHOR]

This study investigated the effects of waste ceramic powder on both the mechanical and microstructural properties of mortar. The study explored the utilization of Al2O3-SiO2 nanoparticles in mortar as cement replacement. Four mixes containing ceramic nanoparticles (0, 20, 40, and 60%) were prepared. The mortar specimens were tested for compressive strength. The role of ceramic waste powder was investigated through the analysis of microstructure in terms of scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and differential thermal analysis. The results revealed that the replacement of Al2O3-SiO2 nanoparticles to the mortar matrix had significantly enhanced the compressive strength. At 90 days, the compressive strength was in the range of 44.7-58.8 MPa. The results were validated through a microstructure test. The mortar with 40% of ceramic replacement showed better performance in terms of C-S-H production from active siliceous containing excessive calcium hydroxide content. [ABSTRACT FROM AUTHOR]

In this study, the effect of waste polypropylene carpet fibres and palm oil fuel ash (POFA) on the mechanical and microstructural properties of concrete exposed to elevated temperatures was investigated. Concrete samples were exposed to high temperatures up to 800∘C then cooled to ambient temperature before tests. Four mixes containing carpet fibres (0 and 0.5%) and POFA (0 and 20%) were prepared. Mass loss, residual ultrasonic pulse velocity, compressive strength, scanning electron microscopy, X-ray diffraction and differential thermal analysis were performed to investigate the effects of carpet fibres and POFA on the performance of the concrete at elevated temperatures. The results showed that both carpet fibres and POFA were associated with a significant enhancement in the fire resistance and residual compressive strength and also eliminating the explosive spalling behaviour of the concrete at elevated temperatures. Furthermore, the role of carpet fibres and POFA is discussed through the microstructural analysis and fibre-matrix interactions as function of heat treatment. [ABSTRACT FROM AUTHOR]

The effect of high volume nano palm oil fuel ash in the mortar was investigated. This study covers basic properties like the morphology of the composite, the hydration temperature, strength activity index, thermal conductivity and microstructure properties with regards to the variations in the mix design process of mortar. The effects of fineness of the ash on the strength properties of mortar were also investigated. To get a better performance in terms of strength development, the ash used has gone through heat treatment and was ground up to less than 1 μm. The incorporation of more than 80% nano size palm oil fuel ash as cement replacement has produced a mortar having a compressive strength more than OPC mortar at a later age. The overall results have revealed that the inclusion of high volume nano palm oil fuel ash can produce a mortar mix with high strength, good quality and most importantly that is more sustainable. [ABSTRACT FROM AUTHOR]

• Nanomaterials can enhance the sustainability performance of concrete. • Strength performance of concrete highly influenced by nanomaterials type and content. • Environmental fitness of nanomaterials based concrete is discussed. • Engineering properties and microstructure analysis of modified concrete are discussed. Negative effects of carbon dioxide (CO 2) emissions due to rapid development in several countries worldwide are of increasing concern for the sustainable growth. To overcome such problem, the production of less clinker-based modified concretes with lower levels of CO 2 emission became challenging in the building sectors. Such concretes can offer satisfactory strength performance and durability in the construction sector. Meanwhile, various nanomaterials incorporated concretes generated immense interests for attaining the sustainability objectives in the civil engineering field. Based on these factors, a comprehensive sustainability assessment of diverse nanomaterials included cement-based concretes was made. In addition, the mechanisms behind the influence of different nanomaterials on the strength characteristics, workability and durability performances of the proposed improved concretes were examined. The past progress, recent drifts, ongoing challenges, effects on environmental sustainability, pros and cons of these nanomaterials-activated cement-based concretes were emphasized. [ABSTRACT FROM AUTHOR]

Airborne Microplastics (MPs), an emerging environmental issue, have gained recent attention due to their newfound presence in indoor environments. Utilizing the Web of Science database for literature collection, the paper presents a comprehensive review of airborne MPs including emission sources, assessment methods, exposure risks, and mitigation strategies. This review delves into the diverse sources and mechanisms influencing indoor airborne MP pollution, underscoring the complex interplay between human activities, ventilation systems, and the characteristics of indoor environments. Major sources include the abrasion of synthetic textiles and the deterioration of flooring materials, with factors like carpeting, airflow, and ventilation significantly impacting MP levels. Human activities, such as increased movement in indoor spaces and the intensive use of plastic-based personal protective equipment (PPE) post-pandemic, notably elevate indoor MP concentrations. The potential health impacts of airborne MPs are increasingly concerning, with evidence suggesting their role in respiratory, immune, and nervous system diseases. Despite this, there is a scarcity of information on MPs in diverse indoor environments and the inhalation risks associated with the frequent use of PPE. This review also stresses the importance of developing effective strategies to reduce MP emissions, such as employing HEPA-filtered vacuums, minimizing the use of synthetic textiles, and enhancing indoor ventilation. Several future research directions were proposed, including detailed temporal analyses of indoor MP levels, interactions of MP with other atmospheric pollutants, the transport dynamics of inhalable MPs (≤10 μm), and comprehensive human exposure risk assessments. [Display omitted] [ABSTRACT FROM AUTHOR]

The recycling of millions of tons of glass bottle waste produced each year is far from optimal. In the present work, ground blast furnace slag (GBFS) was substituted in fly ash-based alkali-activated mortars (AAMs) for the purpose of preparing glass bottle waste nano-powder (BGWNP). The AAMs mixed with BGWNP were subsequently subjected to assessment in terms of their energy consumption, economic viability, and mechanical and chemical qualities. Besides affording AAMs better mechanical qualities and making them more durable, waste recycling was also observed to diminish the emissions of carbon dioxide. A more than 6% decrease in carbon dioxide emissions, an over 16% increase in compressive strength, better durability and lower water absorption were demonstrated by AAM consisting of 5% BGWNP as a GBFS substitute. By contrast, lower strength was exhibited by AAM comprising 10% BGWNP. The conclusion reached was that the AAMs produced with BGWNP attenuated the effects of global warming and thus were environmentally advantageous. This could mean that glass waste, inadequate for reuse in glass manufacturing, could be given a second life rather than being disposed of in landfills, which is significant as concrete remains the most commonplace synthetic material throughout the world. [ABSTRACT FROM AUTHOR]

This paper presents the experimental results on the behavior of fly ash geopolymer concrete incorporating bamboo ash on the desired temperature (200 °C to 800 °C). Different amounts of bamboo ash were investigated and fly ash geopolymer concrete was considered as the control sample. The geopolymer was synthesized with sodium hydroxide and sodium silicate solutions. Ultrasonic pulse velocity, weight loss, and residual compressive strength were determined, and all samples were tested with two different cooling approaches i.e., an air-cooling (AC) and water-cooling (WC) regime. Results from these tests show that with the addition of 5% bamboo ash in fly ash, geopolymer exhibited a 5 MPa (53%) and 5.65 MPa (66%) improvement in residual strength, as well as 940 m/s (76%) and 727 m/s (53%) greater ultrasonic pulse velocity in AC and WC, respectively, at 800 °C when compared with control samples. Thus, bamboo ash can be one of the alternatives to geopolymer concrete when it faces exposure to high temperatures. [ABSTRACT FROM AUTHOR]