What is flakiness index?

The flakiness index is a measure used primarily in the construction and civil engineering industries, particularly in the evaluation of aggregate materials used in road and pavement construction. It quantifies the percentage of flaky particles present in a sample of aggregate. Flaky particles are defined as those having a thickness much smaller than their width and length.

The flakiness index is crucial because the shape and size of aggregates significantly affect the strength, durability, and stability of the constructed road or pavement. Aggregates with a high flakiness index tend to have less mechanical strength and more susceptibility to breaking down under heavy loads, leading to a less durable road surface.

To determine the flakiness index, aggregates are passed through a series of standard sieves with elongated slots. Particles that pass through these slots are considered flaky. The proportion of flaky particles relative to the total sample gives the flakiness index. A lower flakiness index indicates a higher quality aggregate that is likely to perform better in construction applications. This measure helps in ensuring that the aggregates used in construction projects meet the necessary specifications for optimal performance and longevity.