Aggregate Properties
Aggregate Properties - Related Videos
10:10
Aggregates for Concrete and Asphaltic Mixes
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2023
Source: Roberto Leon, Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA Concrete and asphalt are by far the most common construction materials used today. Concrete is a composite material consisting of cement, water, air, coarse aggregate, and fine aggregates. Fine aggregates are typically sands and coarse aggregates are natural or crushed rocks. Chemical admixtures to modify certain specific properties are also commonly used (i.e., superplasticizers to make the...
08:04
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
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Cited by 1 •
2020
Here, we present a protocol for parametrizing a tight-binding excitonic Hamiltonian for calculating optical absorption spectra and optoelectronic properties of molecular materials from first-principles quantum chemical calculations.
09:14
Tracking Hypoxic Signaling within Encapsulated Cell Aggregates
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Cited by 10 •
2011
A method for photo-encapsulation of cells in a crosslinked PEG hydrogel is described. Hypoxic signaling within encapsulated murine insulinoma (MIN6) aggregates is tracked using a fluorescent marker system. This system allows serial examination of cells within a hydrogel scaffold and correlation of hypoxic signaling with changes in cell phenotype.
07:16
Physical Properties Of Minerals II: Polymineralic Analysis
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2023
Source: Laboratory of Alan Lester - University of Colorado Boulder The physical properties of minerals include various measurable and discernible attributes, including color, streak, magnetic properties, hardness, crystal growth form, and crystal cleavage. These properties are mineral-specific, and they are fundamentally related to a particular mineral’s chemical make-up and atomic structure. This video examines several physical properties that are useful in field and hand sample mineral...
11:57
Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans
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Cited by 7 •
2017
The goal of the method presented here is to explore protein aggregation during normal aging in the model organism C. elegans. The protocol represents a powerful tool to study the highly insoluble large aggregates that form with age and to determine how changes in proteostasis impact protein aggregation.
FAQs
Particle-size distribution controls how efficiently aggregate particles fit together. A suitable range of sizes can improve packing by allowing smaller particles to occupy spaces between larger ones, while an unfavorable distribution can increase voids and alter binder requirements. In concrete and asphalt, these changes influence workability, stiffness, and the mixture’s ability to carry loads.
Particle shape and surface texture influence both particle interlock and contact with the binder. These characteristics affect how aggregates interact with one another, as well as the resulting workability, bonding, and stiffness of concrete or asphalt. Evaluating them helps engineers select materials that support the intended performance of the finished mixture.
Porosity provides space within aggregate particles that can interact with water and binder, while moisture content describes the material’s water condition during use. Together, they affect absorption and mixture behavior. Measuring these characteristics helps engineers account for how aggregates may influence bonding, workability, durability, and the consistency of concrete or asphalt mixtures.
Engineers commonly assess aggregates through grading, specific-gravity, absorption, and strength tests. Grading examines particle-size distribution, while specific-gravity and absorption measurements characterize density and interaction with water. Strength testing evaluates resistance to mechanical demands, and abrasion testing indicates resistance to wear. The combined results support material selection and mixture optimization.
Engineers compare measured aggregate characteristics with the performance needs of the intended application. Results from grading, density, absorption, abrasion, and strength evaluations help identify materials that can provide suitable packing, bonding, durability, stiffness, and load-bearing capacity. This information also supports mixture optimization and improves predictions of how the material will perform in infrastructure.
Aggregate properties connect the characteristics of granular particles with the behavior of engineered mixtures and finished infrastructure. Their effects on packing, bonding, stiffness, abrasion resistance, and load-bearing capacity can influence durability and safety. Systematic evaluation allows engineers to select appropriate materials and design concrete or asphalt mixtures for reliable performance.