Aggregate Strength

Uniform size aggregate
1. Friction at few points of contact2. Poor interlocking3. High percentage of voids
Well-graded aggregate
1. Friction at many points of contact2. Excellent interlocking3. Very few voids
Mixture of course and fine aggregate
1. Friction at many points of contact2. Good interlocking3. Few voids4. Economical preparation
1.The strength of the aggregate increases with the maximum size of the aggregate.2.Well-graded aggregates are stronger than not well-graded ones.3.Strength is increased by rough particle surfaces due to the greater friction.

4.The shearing strength of the aggregate (of any shape, size, and gradiation) is increased by compaction, especially by vibration.

5.The strength created through interlocking is increased by the more flat, broken faces the particles have. Flat faces fit together with more contact and more compactly than if the particles are rounded, however this doesn’t imply the particles should be flat, since flat particles result in a lack of strength.