Flakiness And Elongation Index Essay
Flakiness & Elongation index is one of the most prominent criteria that govern behavior and performance of aggregate in the bituminous mixes. The strength and serviceability requirements of bituminous mixture such as Stability, Flow, Voids in Total mix (VTM), Voids Filled with Bitumen and (VFB) highly depend on the physical properties of aggregates. This study conducted by observing the effect of flakiness & elongated index by adding different percentages from 0% to 50% of flaky & elongated aggregates of different sieve with required quantity to the bituminous mixes. The method of Marshall Mix design is adopted for this purpose.
The change in rotation angle of coarse aggregate was found to correlate well with the internal resistance …show more content…
At 0% the value of density is 2.34 g/cc, but at 50 % flakiness & elongation index is 2.226%.
From the results that are obtained from this study it has been concluded that flakiness & elongation index should be kept below 40% for a better strength and durability.
• With increasing flakiness & elongation index, stability decreases.
• Increase of flaky & elongation index decreases the stability due to negative performance of flaky & elongated aggregates in the mix.
• The value of flow decreases with increasing elongation index.
• Flow is decreasing with increase in flakiness & elongation index in the mix, because due to lack of degree of interlocking.
• Void filled with bitumen (VFB) is a property that is highly related to VTM. The more void percentage in the mix, decreases the strength and the more voids are filled by bitumen. So they are inversely proportional.
• The value of VMA is decreasing with increasing of flakiness & elongation index.
• VTM is decreasing with increasing of elongation index.
• The value of density is decreasing with increasing of flakiness & elongation