High alumina aggregate is a versatile construction material that is gaining popularity due to its high durability and strength. With growing infrastructure needs and urbanization, there is increasing demand for building materials that can withstand heavy usage and extreme weather conditions over long periods of time. High alumina aggregate fits the bill perfectly as it offers outstanding resistance to wear and corrosion. In this article, we delve deeper into the properties and uses of high alumina aggregate.
Properties of High Alumina Aggregate
High Alumina Aggregate derives its strength and durability from its chemical composition. It is composed mainly of alumina (Al2O3), which makes up more than 70% of its content. Alumina is one of the hardest natural materials and imparts high compression and flexural strength to concrete when used as aggregate. Some key properties of high alumina aggregate include:
– High compressive strength: Concrete made with high alumina aggregate can achieve compressive strengths exceeding 60 MPa. This is much higher than normal concrete.
– Excellent wear resistance: With a Mohs hardness of 9 (similar to corundum), high alumina aggregate is highly resistant to abrasion, making it suitable for applications with heavy vehicular traffic.
– Corrosion resistance: The inert alumina composition provides resistance to chemical attacks from acids, alkalis, salts and other corrosive agents. This prevents concrete from degradation.
– Low thermal expansion: High alumina aggregate maintains dimensional stability during temperature fluctuations and resists cracking from freeze-thaw cycles.
– Non-porous surface: Its dense structure means it does not absorb water or allow permeability through the aggregate concrete interface.
Areas of Application
Given the superior mechanical and durability properties, high alumina aggregate has applications across many industries where long-lasting infrastructure is required. Some key application areas include:
Road Construction
High Alumina Aggregate concrete is increasingly being used to pave roads, highways and bridges experiencing heavy traffic loads. It can withstand the combined effects of wear, erosion and environmental exposures better than normal concrete. The Taiwan High Speed Rail is a prime example where high alumina concrete tracks are durable after decades of use.
Industrial Flooring
Warehouses, manufacturing facilities and processing plants require floors that can withstand continuous heavy loading from forklifts, cranes and heavy machinery. High alumina concrete floors have high compressive strength and are non-porous, making them resistant to impacts and chemicals spills.
Airports
The runways and taxiways at many airports worldwide are now constructed using high alumina concrete for its ability to retain smoothness under frequent use by jet aircraft. It also resists jet fuel spills and de-icing chemicals better than conventional concrete.
Wastewater Treatment Plants
In the harsh environments of wastewater treatment facilities, high alumina concrete endures intensive abrasion from sludge and resists attacks from acids, alkalis and sulfides in the wastewater. It is used for floors, trenches and containment walls.
Other common applications include sea ports, heavy duty floors in steel and mining plants, overlay concrete wearing courses for bridge and tunnel approaches, locks for canal infrastructure, and reservoirs.
Advantages over Alternative Materials
While high performance and more expensive initially, high alumina concrete offers clear advantages over normal concrete and other materials in the long run:
– Longer lifespan and reduced maintenance: Initial investment is offset by avoiding frequent repairs and early replacements required with weaker materials.
– No corrosion of reinforcements: Normal concrete often causes corrosion of embedded steel due to permeability issues. High alumina avoids this costly problem.
– Enhanced safety: Critical infrastructure made of high alumina aggregate is less prone to failure from overloading or corrosive chemicals/environments.
– Environmental friendliness: More durable construction reduces needs for resource intensive repair works and prevents ground/water pollution from material degradation.
– Aesthetic properties: Surface retains its initial smoothness and color for long without needing overlay layers.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
