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Concrete is classified as a multi-composite material comprising three phases: coarse aggregate, mortar, and interfacial transition zone (ITZ). Fine and coarse aggregates occupy approximately 70-85% by volume, of which coarse aggregate typically constitutes more than two-thirds of the total quantity of aggregate by volume. The current study investigates the concrete performance produced using various recycled construction and by-product industrial waste coarse aggregates. Six types of coarse aggregates: manufactured limestone, quartzite, natural scoria, by-product industrial waste aggregate, and two sources of recycled concrete aggregates with densities ranging from 860 to 2300 kg/m and with different strength properties were studied. To determine the coarse aggregate contribution to the overall concrete performance, lean and rich concrete mixtures (Mix 1 and Mix 2) were used. Mix 1 (lean mixture) consisted of a ratio of water to cement (w/c) of 0.5 and cement content of 300 kg/m, whereas a higher quantity of cement of 500 kg/m and a lower w/c ratio of 0.3 were used for Mix 2 (rich mixture). The results showed that while the compressive strength for different aggregate types in Mix 1 was comparable, the contribution of aggregate to concrete performance was very significant for Mix 2. Heavyweight aggregate produced the highest strength, while the lightweight and recycled aggregates resulted in lower mechanical properties compared to normal weight aggregates. The modulus of elasticity was also substantially affected by the coarse aggregate characteristics and even for Mix 1. The ACI 363R-92 and CSA A23.3-04 appeared to have the best model for predicting the modulus of elasticity, followed by the ACI-318-19 (density-based formula) and AS-3600-09. The density of coarse aggregate, and hence concrete, greatly influenced the mechanical properties of concrete. The water absorption percentage for the concrete produced from various types of aggregates was found to be higher for the aggregates of higher absorption capacity.
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http://dx.doi.org/10.3390/ma15248985 | DOI Listing |
J Hazard Mater
September 2025
State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address:
While humic acids (HAs) are known to modulate heavy metal behavior, their profound heterogeneity across soil aggregate fractions remains overlooked. Crucially, whether HA origin within distinct soil aggregates differentially governs heavy metal speciation and bioavailability is unknown-creating a critical knowledge gap for targeted soil remediation. This study deciphers, for the first time, how aggregate-specific HAs control cadmium (Cd) and lead (Pb) dynamics.
View Article and Find Full Text PDFJ Phys Chem B
September 2025
Department of Chemistry, IIT Jodhpur, Jodhpur, Rajasthan 342037, India.
The dynamics of the aggregated light-harvesting complex (LHCII) associated with its antenna pigments can be crucial for a transition between light-harvesting and dissipative states, which is pivotal for nonphotochemical quenching (NPQ). To this end, aggregation of pigment-binding LHCII monomers and PsbS-associated trimers in neutral and low lumenal pH respectively, has been investigated when embedded in the plant thylakoid membranes, using coarse-grained molecular dynamics simulations. Both pigment-binding LHCII monomers and PsbS-associated trimers dynamically form and break dimers and higher-order aggregates in thylakoids within the simulation time.
View Article and Find Full Text PDFIEEE Trans Med Imaging
September 2025
Computed Tomography (CT) to Cone-Beam Computed Tomography (CBCT) image registration is crucial for image-guided radiotherapy and surgical procedures. However, achieving accurate CT-CBCT registration remains challenging due to various factors such as inconsistent intensities, low contrast resolution and imaging artifacts. In this study, we propose a Context-Aware Semantics-driven Hierarchical Network (referred to as CASHNet), which hierarchically integrates context-aware semantics-encoded features into a coarse-to-fine registration scheme, to explicitly enhance semantic structural perception during progressive alignment.
View Article and Find Full Text PDFLangmuir
September 2025
Polymer Research Institute, State Key Laboratory of Advanced Polymer Materials, Sichuan University, Chengdu 610065, China.
Switchable surfactants exhibit broad application potential due to their reversible response to external stimuli. The reversible mechanism of the CO-switchable surfactant ('-dodecyl-, -dimethyl-acetamidines, DDA) solubilization polycyclic aromatic hydrocarbons (PAHs) and the microscopic dynamic behavior of emulsification/demulsification were systematically studied using coarse-grained molecular dynamics simulations. The dynamic transition processes of protonation (DDA to DDA) and deprotonation (DDA to DDA) were successfully simulated.
View Article and Find Full Text PDFSci Rep
August 2025
Department of Structural Engineering, Faculty of Engineering, Cairo University, Giza, Egypt.
Recycling crushed clay bricks as both coarse and fine aggregates has shown promising potential for producing eco-friendly concrete, helping to reduce the industry's environmental footprint while promoting the sustainable reuse of waste materials. However, the inherent variability of these aggregates can lead to inconsistent concrete performance, emphasizing the need for a thorough investigation to assess their suitability for construction applications. For this purpose, a number of concrete mixtures incorporating crushed clay bricks as coarse and/or fine aggregates were produced and tested in this study.
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