Safety First, Deadlines Before? Health & Safety

Majeed Azam

QAQC ON asphalt WORKS

Asphalt is produced in a plant that Heats, Dries and Mixes Aggregate, Bitumen and Sand into a composite mix. It is then applied through a paving machine on site as a solid material at a nominated or required thickness, relative to the end use.

It is a binder mixed with an aggregate creating asphalt cement that binds the stone, sand, and gravel, resulting in the pavement for our roads, highways and airfields. There is more thought that goes into asphalt mix designs than do concrete ones. Determining an optimum asphalt blend involves various laboratory tests, calculations, and determinations to find the optimum mix proportions. It is important for a mix to have the correct proportions. Following tests are performed to evaluate the quality of

• Asphalt Site Sampling and Temperature Monitoring

•Binder content

Quantitative determination of the asphalt binder content of HMA mixtures and pavement samples is necessary for many reasons, including: quality control, specification acceptance, and mixture evaluation studies. HMA that has too much asphalt binder can experience problems such as bleeding, lowered skid resistance, and lowered resistance to permanent deformation (rutting and shoving.

•% Air voids

Asphalt consists of four main materials: bitumen, aggregate, fillers (fine particles) and air. Asphalt without sufficient air entrapped in the layer will deform under traffic and result in a rutted and rough surface.

•Asphat Coring

Asphalt core cutting test to determine the thickness of the asphalt layer, compaction and other properties.

•Asphalt Softening Point Test: all asphalt is created the same, engineers need to predict how well an asphalt mixture will perform in addition to the maximum load it can support

The determination of softening point helps to know the temperature up to which a bituminous binder should be heated for various road use applications.

•Particle Size Distribution

Portion of aggregate on specified sieves expressed as cumulative percentages by mass passing those sieves.The test is applicable to aggregates recovered after binder extraction.