Objective
For determination of flakiness index of coarse aggregate, where the size of the coarse aggregate are larger than 6.3mm .
Reference Standards
IS : 2386 (Part I) – 1963 – Method of test for aggregates for concrete (Part I) Particle size and shape.
Equipment & Apparatus
- Thickness gauge
- Sieves [63, 50, 40, 31.5, 25, 20, 16, 12.5, 10 & 6.3mm]
- Balance [0-10 kg]
Thickness Gauge
Preparation sample
Surface dry samples is used for the test. A minimum number of 200 pieces of any specified fraction is required to do the test.
Procedure
- The sample is sieved through IS sieve specified in Table shown below.
Dimension of Thickness and Length Gauge - A minimum of 200 pieces of each fraction is taken and weighed.
- In order to separate flaky materials, each fraction is then gauged individually for thickness on a thickness gauge.
- The total amount of flaky material passing the thickness gauge is weighed to an accuracy of 0.1% of the weight of sample.
Calculation
In order to calculate the flakiness index of the entire sample of aggregates, first the weight of each fraction of aggregate passing and retained on the specified set of sieves is noted (Y1, Y2, Y3, Y4…..etc). Each piece of these are tried to be passed through the slot of the specified thickness of the thickness gauge are found and weighed (y1, y2, y3, y4…etc). Then the flakiness index is the percentage of materials passed through the thickness gauge on the various thickness gauges, expressed as a percentage of the total weight of the sample gauged.
Report
Flakiness index is reported in percentage to the nearest whole number
Safety & Precautions
- Use hand gloves while removing containers from oven after switching off the oven.
- Use safety shoes, mask & aprons at the time of test.
- Thoroughly clean & dry the container before testing.
- Special care should be taken that no outer air enters when using the balance.
- All parts of the equipment should always be kept clean.
- After the end of the test sieve should be clean by smooth brush.
FI nd EI limit of concrete aggregate
Why in elongation index among 63mm to 50mm aggregate, and 31.5mm to 25mm aggregate dose not test?
In which IS code limit of Fe and ei is given sir?
IS-383
As definition of flakiness index
0.6×mean dia
For example the agreegates retained in 50 mm dia sieve and passed from 63 mm dia sieve will we gauged from the thickness of. 0.6×(50+63) /2 = 33.9
How to know about the guage size with out usung chart.
How to know about the guage size with out usung chart.
What is the maximum limit of elongation index and 10% fine value of aggregates used for stone column?
How the flakiness index is conclude for buildings and which Iscode should be refer for flakiness index
Sir what is the flakiness value for aggregates which is used in highway subgrade
How to calculate combined fi@ei value of 40-31%,20mm -17%,10 Mm -23% having respectively fi&ei value of 23%,43%,37% individual ..
How to calculate this value combined FI &EI
What is the maximum limit of flakiness index
thankyou sir about the informtion, its very useful for the civil engineering student
🙂
Having read this I thought it was really informative. I appreciate you taking the time
and energy to put this content together. I once again find myself spending
a lot of time both reading and leaving comments. But so what, it was still
worthwhile!
what is the max limit of flakiness index sir
35%max limit for fI&
I want to sample image…..Pls sir…..
The IS is using an obsolete British Standard procedure BS 812:105.1 flakiness test using a thickness gauge, It is already superseded by EN 933-3, flakiness index test using bar sieves not a thickness gauge anymore. Mr. Mithun is right, it is the percentage passing on each gauges were calculated and reported as flakiness Index. Because the materials retained on the gauge are not flaky, instead, the materials that passes the gauges are called flaky materials.
Respected sir, please send an article regarding to IS limits for aggregate soil , steel,cement properties. Such as physical, chemical engineering etc. All upper or lower limits.
This is wrong.Flakiness is index is the percentage of materials passed through the thickness gauge out of the total material sieved.
What is the difference between your argument and the Authors statement? In fact the Authors statement is correct, because you may have sieved more weight of material, but you need to take only 200 pieces. So the statement “Material Gauged” is the correct statement.
Author specifies that flakiness index is the % of total retained materials in the corresponding gauge to the total weight of sample, but I think it is the % of materials passed the corresponding gauge to the total weight of sample. Am not I correct?
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