Assessment of mechanical,durability and microstructural properties of geopolymer concrete containing ceramic tile waste

Journal of Material Cycles and Waste Management - The amount of ceramic waste being generated is increasing day by day, and ceramic waste management is one of the most challenging issues for many...     

Strength and durability assessment of concrete containing dolomite quarry waste as fine aggregate

Journal of Material Cycles and Waste Management - The present study focuses on utilizing stockpiled dolomite quarry waste for sustainable and cleaner production of concrete. Natural river sand is...     

Mechanical and durability properties of insulation mortar with rubber powder from waste tires

Fine rubber particles from scrap tires can be used as an insulation material by incorporating with Portland cement mortar. In addition to thermal properties, there are special mechanical and durability properties that are important for the insulation mortar. The addition of rubber particles has negative impact on these properties. The special properties for insulation mortar can be improved using cellulose ether, redispersible polymer powder (RPP), and wood fiber. The objective of this study is to investigate the effects of these additives and the rubber powder on the properties of rubberized insulation mortar. With increasing rubber content, both flexural strength and compressive strength were reduced, but the reduction of flexural strength was not as significant as for the compressive strength. At a fixed rubber content, as the optimal amount of RPP and smaller rubber powder were used, the compressive strength of rubberized mortar satisfied the minimum requirement of the type N mortar. The drying shrinkage of the rubber mortar was about the same as the ordinary cement mortar. The permeability of the rubber mortar was low comparing with that of the ordinary cement mortar. The bond strength of the rubber mortar is low due to the reduced effective bonding surface.     

Effect of addition diatomite powder on mechanical strength,elevated temperature resistance and microstructural properties of industrial waste fly ash-based geopolymer

This study examines the use of fly ash, a thermal power plant waste, and the effect of diatomite, a fossil algae type, on waste-based geopolymers in the production of sustainable geopolymer binders. The effects of 1%, 2%, 3%, 4% and, 5% diatomite substitution on waste-based mortars were investigated. Mortars containing 10% and 12% Na⁺ by weight based on the binder material were cured at 75 °C for 48 h. The flexural and compressive strength, abrasion resistance, determination of ultrasonic pulse velocity, and resistance to high temperatures of geopolymer mortar samples were investigated. In addition, FESEM images, EDX and XRD analyses of geopolymer mortar samples were made, and their microstructures were examined. 2% diatomite substitution increased flexural and compressive strength. In parallel with this situation, it was concluded that the abrasion resistance and ultrasonic pulse velocity of the geopolymer mortar with 2% diatomite substituted increased. In addition, it has been shown in FESEM images that the microstructure has a denser morphology. All geopolymer mortars lost strength after the high temperatures of 300 °C, 600 °C and 900 °C. As a result, it was concluded that diatomite containing highly reactive silica can be used in geopolymer systems.

     

The improvement of strength and microstructural properties of fly ash-based geopolymer by adding elemental aluminum powder

Journal of Material Cycles and Waste Management - In this study, 1, 2, and 3% micronized aluminum powder were used by replacing with fly ash to improve the properties of F class fly ash-based...     

Durability analysis and optimization of a binary system of waste cement concrete and glass-based geopolymer mortar

Journal of Material Cycles and Waste Management - Enormous generation of construction and demolition (C&D) waste along with municipal solid waste (MSW) is required to managed properly for...     

Mechanical and toxicological evaluation of concrete artifacts containing waste foundry sand

The creation of metal parts via casting uses molds that are generally made from sand and phenolic resin. The waste generated after the casting process is called waste foundry sand (WFS). Depending on the mold composition and the casting process, WFS can contain substances that prevent its direct emission to the environment. In Brazil, this waste is classified according to the Standard ABNT NBR 10004:2004 as a waste Class II (Non-Inert). The recycling of this waste is limited because its characteristics change significantly after use. Although the use (or reuse) of this byproduct in civil construction is a technically feasible alternative, its effects must be evaluated, especially from mechanical and environmental points of view. Thus, the objective of this study is to investigate the effect of the use of WFS in the manufacture of cement artifacts, such as masonry blocks for walls, structural masonry blocks, and paving blocks. Blocks containing different concentrations of WFS (up to 75% by weight) were produced and evaluated using compressive strength tests (35 MPa at 28 days) and toxicity tests on Daphnia magna, Allium cepa (onion root), and Eisenia foetida (earthworm). The results showed that there was not a considerable reduction in the compressive strength, with values of 35 ± 2 MPa at 28 days. The toxicity study with the material obtained from leaching did not significantly interfere with the development of D. magna and E. foetida, but the growth of the A. cepa species was reduced. The study showed that the use of this waste in the production of concrete blocks is feasible from both mechanical and environmental points of view.     

Recycling of waste glass as a partial replacement for fine aggregate in concrete

Waste glass creates serious environmental problems, mainly due to the inconsistency of waste glass streams. With increasing environmental pressure to reduce solid waste and to recycle as much as possible, the concrete industry has adopted a number of methods to achieve this goal. The properties of concretes containing waste glass as fine aggregate were investigated in this study. The strength properties and ASR expansion were analyzed in terms of waste glass content. An overall quantity of 80 kg of crushed waste glass was used as a partial replacement for sand at 10%, 15%, and 20% with 900 kg of concrete mixes. The results proved 80% pozzolanic strength activity given by waste glass after 28 days. The flexural strength and compressive strength of specimens with 20% waste glass content were 10.99% and 4.23%, respectively, higher than those of the control specimen at 28 days. The mortar bar tests demonstrated that the finely crushed waste glass helped reduce expansion by 66% as compared with the control mix.     

Valorization of marine sediments in geopolymer mortars: physico-mechanical,microstructural and environmental investigations at laboratory scale

Journal of Material Cycles and Waste Management - The high consumption of natural sand and the accumulation of mineral wastes in landfills such as dredged sediments make it necessary to valorize...     

废旧胶粉的制作及利用现状

简要介绍废旧胶粉的制造方法,以及胶粉在实际生产、生活当中的应用现状。提高废旧胶粉的再利用技术,拓展其应用领域,是节约资源、保护环境,促进国民经济增长方式转变和可持续发展的重要措施。     

Elaboration of geopolymer binder from pharmaceutical glass waste and optimization of its synthesis parameters

Journal of Material Cycles and Waste Management - The objective of this study is to manufacture a new geopolymer binder from pharmaceutical glass waste as a main raw material. The geopolymer...     

Geotechnical and leaching properties of flowable fill incorporating waste foundry sand

Waste foundry sand (WFS) can be converted into flowable fill for geotechnical applications. In this study, WFS samples were obtained from 17 independent metal casting facilities with different casting processes, thus representing a good range of WFS properties. The laboratory studies include physical, geotechnical and leaching properties of flowable fills consisting of WFS, cement, and fly ash mixed to different water contents. The main properties measured include WFS physical properties (density, particle gradation, grain shape, and fine content), WFS flowable fill geotechnical properties (unconfined compressive strength, hydraulic conductivity, setting time, and bleeding), and the fill's leaching properties (heavy metals and organics in the bleed water and the leachate extracted from hardened WFS flowable fills). The test results indicate that in terms of the physical properties, most of the data fall within narrow ranges, although data from the copper/aluminum-based WFS samples might fall beyond the ranges. Geotechnical properties of WFS flowable fills in both fresh and hardened phases were verified conforming to the features of specified flowable fills. Material leaching analyses indicate that the toxicity of WFS flowable fills is below regulated criteria. A mix formulation range originated from this study is proposed for the design of WFS made flowable fill.     

Performance evaluation of dolomite production waste in development of sustainable concrete: hardened properties and ecological assessment

Journal of Material Cycles and Waste Management - Dolomite production waste is a by-product generated by dolomite mining, causing environmental pollution and other associated issues worldwide. In...     

Stochastic modelling of landfill processes incorporating waste heterogeneity and data uncertainty

A landfill is a very complex heterogeneous environment and as such it presents many modelling challenges. Attempts to develop models that reproduce these complexities generally involve the use of large numbers of spatially dependent parameters that cannot be properly characterised in the face of data uncertainty. An alternative method is presented, which couples a simplified microbial degradation model with a stochastic hydrological and contaminant transport model. This provides a framework for incorporating the complex effects of spatial heterogeneity within the landfill in a simplified manner, along with other key variables. A methodology for handling data uncertainty is also integrated into the model structure. Illustrative examples of the model's output are presented to demonstrate effects of data uncertainty on leachate composition and gas volume prediction.     

Utilization of waste glass in ECO-cement: strength properties and microstructural observations

Waste glass creates a serious environmental problem, mainly because of the inconsistency of the waste glass streams. The use of waste glass as a finely ground mineral additive (FGMA) in cement is a promising direction for recycling. Based on the method of mechano-chemical activation, a new group of ECO-cements was developed. In ECO-cement, relatively large amounts (up to 70%) of portland cement clinker can be replaced with waste glass. This report examines the effect of waste glass on the microstructure and strength of ECO-cement based materials. Scanning electron microscopy (SEM) investigations were used to observe the changes in the cement hydrates and interface between the cement matrix and waste glass particles. According to the research results, the developed ECO-cement with 50% of waste glass possessed compressive strength properties at a level similar to normal portland cement.     

Reuse of wood ash from biomass combustion in non-structural concrete: mechanical properties,durability, and eco-efficiency

Journal of Material Cycles and Waste Management - Wood biomass fly ash can contribute to a more sustainable urban infrastructure, but requires efficient recycling strategies. This paper...     

Investigating mechanical properties and durability of concrete containing recycled rubber ash and fibers

This article investigates the suitability of utilizing end of life rubber tyre particles in concrete as fine aggregate. Rubber ash and rubber fibers were used to develop two series of rubber ash concrete (series I) and hybrid concrete (series II) mixes. The natural fine aggregate was replaced by rubber ash (by volume of 5%, 10%, 15% and 20%) in series I; whereas in series II, the amount of rubber ash was kept constant at 10% and rubber fiber was introduced as replacement of fine aggregate (by volume of 5%, 10%, 15%, 20% and 25%). The concrete mixes were evaluated for compressive strength, flexural strength, resistance to impact loading, fatigue loading, water penetration and shrinkage strain was evaluated. It was observed that inclusion of rubber ash resulted in the improvement of impact resistance of concrete. The results also show that up to 10% rubber ash and rubber fibers can be utilized as fine aggregate to develop feasible and durable rubberized concrete pavements, crash barriers and paver blocks.

     

Influence of ferrochrome ash on mechanical and microstructure properties of ambient cured fly ash-based geopolymer concrete

Journal of Material Cycles and Waste Management - Earlier studies indicated that the reactive MgO reduces shrinkage crack and porosity, and accelerates the hydration and strength development....     

Mechanical properties and microstructure of cement mortars incorporating Cd-zeolitized fly ash

Journal of Material Cycles and Waste Management - A solid enriched with NaA zeolite was synthesized from a coal fly ash, and the so-obtained zeolitized material was used as ion exchanger for...     

Mechanical and thermal properties of bottom ash-based porous geopolymer as thermal insulation material for construction

Journal of Material Cycles and Waste Management - A geo-polymer is a cement-like material that can be used instead of Portland cement, requiring less energy, and emitting less CO2 in its...