Evaluation of Aggregate Sources
Civil engineers select aggregates for how they meet specific project requirements, rather than their geologic history. The physical and chemical properties of rocks determine acceptability of an aggregate. Cost and availability are also key to consider when selecting an aggregate. Often, the wisest decision is finding out how to use locally available material in the most cost-effective manner.
Potential aggregate sources are evaluated for:
1. The quality of their larger pieces
2. The nature and amount of fine material
3. The gradation of aggregate
Drilling Cores / Trial Blasts – Investigate the extent and quality of rock in the quarry.
Cores and trial blasts also evaluate:
1. Grading
2. Particle Shape
3. Soundness
4. Durability
5. Amount of Fine Material
Cores are examined petrographically for:
1. General Quality
2. Suitability for Various Uses
3. Amount of Deleterious Materials
Sand and gravel pits are evaluated by:
1. Collecting Samples
2. Performing a Sieve Analysis
In an aggregate:
A high amount of large gravel and cobble sizes = NEED FOR CRUSHING
A high amount of fine material = NEED FOR WASHING
How aggregate can be used in a structure:
1. Used as a Base Material
2. Asphalt Concrete
3. Portland Cement Concrete
No comments:
Post a Comment