What material is used in base course?

The base course is generally com- posed of granular material such as crushed aggregate, gravel, selected soil, or a mix- ture of selected soil and aggregate.

What is asphalt base made of?

The base layer may consist of unbound aggregate, bitumen-, or cement-bound aggregate. The bound layers may be conventional dense-graded asphalt, lean concrete, or cement-treated; or open-graded asphalt or concrete designed to promote lateral drainage within the pavement structure.

What is HMA base course?

Base course. This is the layer directly below the surface course and generally consists of aggregate (either stabilized or unstabilized) or HMA.

What is asphalt concrete base?

Asphalt concrete base (ACB), also called asphalt treated base (ATB), is a dense-graded HMA with a larger nominal maximum aggregate size (1 inch) intended for use as a base course or binder course (see Figure 1).

What is aggregate base material?

Aggregate base is a construction aggregate typically composed of crushed rock capable of passing through a 20 millimetres (3⁄4 in) rock screen. The component particles will vary in size from 20 mm down to dust. The material can be made of virgin (newly mined) rock, or of recycled asphalt and concrete.

How thick should base course be?

The base course is a compacted granular fill used to build up areas, set levels and provide a strong, stable layer to support the laid paver. Fill in the base course no thicker then 100mm and compact to a uniform dense condition, especially around manholes and kerbs (if more than 100mm is needed compact in layers).

What are the components of asphalt concrete?

Asphalt concrete is a mixture mainly composed of mineral aggregates, asphalt binder, and additive, and has been widely applied in pavement construction. As an adhesive material, asphalt binder is considered to have predominant effects and contributions on whole asphalt pavement performance.

What is concrete base course?

Base course is a layer of the pavement structure immediately beneath the surface course. It typically consists of high quality aggregate such as crushed gravel, crushed stone, or sand that provides a uniform foundation support and an adequate working platform for construction equipment.

What can I use for asphalt base?

Base materials vary by region and can be crushed stone or “conbit” (recycled concrete and asphalt—it’s crushed and reused). Crushed coarse materials like these have jagged surfaces so they’ll compact and lock together in a tough, settle-resistant matrix. A binder like cement dust may be added to hold it all together.

What type of aggregate is used in asphalt?

Asphalt is a mixture of aggregates, binder and filler, used for constructing and maintaining roads, parking areas, railway tracks, ports, airport runways, bicycle lanes, sidewalks and also play- and sport areas. Aggregates used for asphalt mixtures could be crushed rock, sand, gravel or slags.