Aggregates are an essential part of construction materials, providing the foundation for various building and infrastructure projects. These materials—such as sand, gravel, and crushed stone—are mixed with binding agents like cement to form concrete or asphalt. Aggregates add strength, stability, and durability to structures, making them a key component in construction.
In this blog, we’ll explore the different types of aggregates and how they’re used in a variety of construction projects.
Natural Aggregates
Natural aggregates come directly from natural sources like rivers, quarries, or gravel pits. These are some of the most commonly used materials in construction due to their availability and affordability. The most common types include:
Sand
- Sand is a fine material made up of tiny rock and mineral particles, primarily quartz. It is widely used for:
- Concrete production: Sand is a key ingredient in concrete, working as the fine aggregate that binds with cement and coarse aggregates.
- Mortar for masonry: When mixed with cement, sand forms mortar, which is used for laying bricks and blocks.
- Fill material: Sand is often used to fill gaps and level surfaces during construction.
Gravel
- Gravel consists of small, rounded stones and is typically sourced from riverbeds or quarries. Its uses include:
- Base for roads and driveways: Gravel provides stability and drainage, making it ideal as a base layer for roads.
- Drainage systems: It’s often used in drainage solutions like French drains due to its ability to let water pass through.
- Concrete aggregate: Gravel is used as a coarse aggregate in concrete, combined with sand to add strength.
Crushed Stone
- Crushed stone is made by breaking down large rocks into smaller, angular pieces. It has several uses:
- Sub-base for roads: Crushed stone is used as a base layer under asphalt or concrete roads.
- Railway ballast: Its angular shape helps lock the particles together, making it ideal for use in railway tracks.
- Landscaping: Crushed stone is often used for decorative purposes, such as in gardens or driveways.
Recycled Aggregates
Recycled aggregates are made from used construction materials like demolished concrete or asphalt. These materials are processed and reused, offering an environmentally friendly alternative to natural aggregates.
Recycled Concrete Aggregate (RCA)
- RCA is produced by crushing old concrete structures, reducing waste, and preserving natural resources. RCA is used in:
- Road construction: It is often used as a sub-base for roads, highways, and parking lots.
- Backfilling: RCA can be used to fill trenches or around pipes.
- New concrete: Sometimes, RCA is mixed with natural aggregates to create new concrete.
Recycled Asphalt Pavement (RAP)
- RAP comes from milling or crushing old asphalt pavement and is reused in new asphalt mixes, which helps cut costs and reduce waste. It is commonly used for:
- Asphalt paving: RAP is combined with new asphalt to resurface roads.
- Base material: It can also serve as a foundation layer for new roads or parking areas
What Aggregates do Earthworks UK offer?
- MOT Type 1: This aggregate is commonly used for creating a compacted sub-base, suitable for paving projects like driveways or roads. It is essential in laying a firm foundation for surfaces that will carry traffic or heavy loads.
- Recycled Type 1: This type of aggregate includes concrete, brick, and tarmac, typically used in the construction of roads, paths, and patios. Its recycled nature makes it a sustainable choice.
- 6F5 Recycled Aggregate: Crushed down to about 75mm, this aggregate is ideal for bulk filling and creating haul roads. It offers strength and durability for heavy-duty construction.
- Chard Flint: Often used for driveways and pathways, Chard Flint gravel provides both decorative appeal and functional durability. It can be applied in a range of landscaping projects.
- South Cerney Stone: This light cream sandstone is smooth and semi-rounded, commonly used for decorative purposes. While it can be used in driveways, it is more prone to breaking than flint.
- Clean Stone: Available in both recycled and quarried varieties, clean stone is versatile for a range of applications, including drainage and backfilling.
- Sharp Sand & Holme Sand: Sharp sand (0-4mm) is primarily used for block paving and slab laying, while Holme Sand is a coarser type ideal for bedding paving stones.
- Stone Dust: This fine aggregate is often used as a base layer for stone pavers, offering a solid foundation for paving projects.
Each type of aggregate serves a specific function in construction, from foundational work to decorative finishes, contributing to both the structural integrity and aesthetic of the project.
If you’re looking for Aggregates for your construction project, give us a call or fill in our online enquiry form to see how we can help supply what you need – whether that’s advice on the best type of aggregate for your project, or calculating how much you need.
