Figure 1 thickness gauge flakiness index indicating sizes of openings. Flakiness index total mass of aggregate pass slots mass of test sample x 100 where. Take the aggregate sample which contains minimum 200 pieces of any fraction. The flakiness index of an aggregate sample is found by seperating the flaky particles and expressing their mass as a percentage of the mass of the sample tested. The percentage of flaky and elongated particles that it contains. From the experiment the mean flakiness index is 38.
Test procedure for determining flakiness index txdot designation. Determination of the flakiness and the elongation index. Compacted weight fill the container in three equal layers, each layer being subjected to 25 strokes with the. Aggregate flakiness index material testing equipment product code uta0450 thickness gauge flakiness index bs bs 812105. Flat and elongated particles of coarse aggregates have a tendency to fracture more easily than. Determine the empty weight m1 and the volume v of the cylinder at 270c. Elongation index wt of aggregate retained on specified gauge total wt of aggregate taken flakiness index is the % by weight of particles whose least. Flakiness index and elongation index test on coarse aggregates. Flakiness and elongation index of aggregate youtube. Each fraction is gauged in turn for thickness on the metal gauge. It is expressed as the percentage by weight of particles in a sample of more than 200 whose smallest dimension is less than 0.
May 08, 20 objective for determination of elongation index of coarse aggregate, where the size of the coarse aggregate are larger than 6. The presence of flaky or elongated particles in excess of 1015% of the weight of coarse aggregate is undesirable. Aggregate particles are classified as flaky when they have a thickness smallest dimension of less than 0. The weight of retained aggregate on each sieve is measured and determined the percentage of retained.
The grid sieve set is used to determine the flakiness index of the aggregate. It is mentioned in the test procedure bismorth that while. This standard sets out a method for determining the flakiness index of an aggregate. Methods of test for aggregates for concrete, part i. The flakiness index of an aggregate sample is found by separating the flaky particles and expressing their mass as a percentage of the mass of the sample tested.
Flakiness and elongation test of aggregate as per is 2386 part 1, content aggregator duration. Elongation index wt of aggregate retained on specified gauge total wt of aggregate taken flakiness index is the % by weight of particles whose least dimension is lesser than 35 of the mean dimension. Flakiness index test is not applicable for aggregates sizes smaller than 6. What is the significance of flakiness index and elongation index. Use this test method to determine the percentage of particles in a coarse aggregate. The aggregate to be classified is separated into seven. Dec 18, 2017 the flakiness index of an aggregate sample is found by separating the flaky particles and expressing their mass as a percentage of the mass of the sample tested. In case of gravel it is determined by its angularity number. This test is not applicable to aggregate passing 6. Aggregate retained on the 75 mm and passing the 4,75 mm sieve is not included in the test. Dec 24, 2018 recommended values of flakiness index.
This test method covers tests for flat particles, elongated particles, or flat and elongated particles in coarse aggregate. Is the combined flakiness and elongation index of aggregate is the numerical sum of separate elongation index and flakiness index. The percentage by weight of flaky particles present in a given test sample. The flakiness index of aggregates is the percentage by weight of particles whose least dimension thickness is less than three fifths 0. This paper describes the importance of the particle shape of aggregates in road structures, and their determination, especially using the flakiness index test. Flakiness index is the percentage by weight of particles in it, whose least dimension i. The flakiness index of course aggregate is defined in percentage by weight of aggregate particles and least dimension thickness of those particles should not be less than 0. This test is for determining the flakiness index of aggregates used in asphalt surface treatments.
Objective for determination of flakiness index of coarse aggregate, where the size of the coarse aggregate are larger than 6. Flakiness sieves, aggregates testing equipment, controls. Retained on flakiness percentage of bakiness index. The method makes reference to a particle size distribution procedure which is required for determination of flakiness index. The elongation index test procedure contains following steps.
Determination of the flakiness and the elongation index for the given aggregate. Elongation index and flakiness index of coarse aggregate bs. An aggregate is classified as being flaky if it has a thickness smallest dimension of less than 0. Pdf determination of the flakiness and the elongation index. This test is not applicable to sizes smaller than 6. Take representative sample of aggregate as required for the test according to maximum size of aggregate and the container required from table.
Aggregate quality for road construction will also influence the road performance. For more information read our blog characteristics of aggregates. The scope of this test is to provide test methods for determining the flakiness index of coarse aggregate. Flakiness index sieve sets bs flakiness index utest. Shape tests on coarse aggregates such as flakiness index and elongation index, its importance in. Flakiness and elongation of aggregates and concrete properties published on december 6, 2016 december 6, 2016 27 likes 9 comments. For crushed aggregate, the particle shape and surface texture depend on the nature of the parent material and on the type of. The test is carried on aggregate sizes between 63 mm and 6. The flakiness index of an aggregate sample is found by separating the flaky particles and expressing their mass. Aggregate is separated into seven sieve fractions from 636. Aug 11, 2014 the flakiness index test fi is not applicable passing 6. Flakiness sieve test set 47d0415 general description used to determine if aggregate particles are to be considered flaky, i. Elongation index and flakiness index of coarse aggregate. What is the significance of flakiness index and elongation.
Pdf determination of the flakiness and the elongation index for. Calculate the flakiness index to the nearest 0,1 as follows. Shape tests of aggregate for highway material construction. Flakiness index test is conducted by using a metal thickness gauge. Uta0410 flakiness index sieve set consists of 7 sieves. Aggregates which are flaky and elongated are detrimental to the higher. The particle shape of aggregate is determined by the percentages of flaky and elongated particles contained in it. Apr 07, 20 flakiness and elongation test of aggregate as per is 2386 part 1, content aggregator duration. For crushed aggregate, the particle shape and surface texture depend on the nature of the parent material and on the type of crusher and its reduction ratio.
Flakiness and elongation of aggregates and concrete properties. The flakiness index of a coarse aggregate is the mass of. All the sieves include an electrostatically painted frame. Determination of elongation index linkedin slideshare. All the sieves include an electrostatically painted frame and stainless steel bars with a 5 mm diameter. Grid sieve set uta uta0420 the grid sieve set is used to determine the flakiness index of the aggregate. The elongation index is found by separating the elongation particles and expressing their mess as a percentage of the mass of sample tested. An adequate quantity of course aggregate is taken such that the minimum number of 200 pieces of any fraction can be tested. Flakiness gauge for classification of aggregate humboldt mfg. Elongation value is 0% because the aggregate is rounded so no any retain value. The test is not applicable to material passing a 6. Determination of the flakiness and the elongation index for the given aggregate sample. The method applies to aggregates having a nominal size not greater than 63.
The aggregate retained on 63mm and passed through 6. Definition of flakiness index and elongation index civil. Mar 03, 2012 the value that we get from this test is 15. Flat and elongated particles of coarse aggregates have a tendency to fracture more easily than other. The elongation index of an aggregate is the percentage by weight of particles whose greatest dimension length is. May 08, 20 objective for determination of flakiness index of coarse aggregate, where the size of the coarse aggregate are larger than 6. Flakiness index and elongation index of coarse aggregates. Flakiness and elongation index of aggregate gilson co. In this text only flat and elongated particles in accordance with the procedure designated in method b will be covered. The particle shape of the aggregate is determined by. The percentage by weight of the elongated particles present in a given test sample. Exp 1 flakiness and elongation index civil engineers pk. Follow these steps to determine the flakiness index. The flakiness index test fi is not applicable passing 6.
The particle shape of aggregates is determined by the percentages of flaky and elongated particles contained in it. Effect of aggregate flakiness on the compressive strength. Pdf determination of the flakiness and the elongation. Please do subscribe to our channel construction technology and management. Elongation index and flakiness index of coarse aggregate bs 812.
Dec 06, 2016 flakiness and elongation of aggregates and concrete properties published on december 6, 2016 december 6, 2016 27 likes 9 comments. Aggregate angularity flakiness elongation index gilson co. Elongation index is the percentage by weight of particles in it, whose largest dimension i. Objective for determination of elongation index of coarse aggregate, where the size of the coarse aggregate are larger than 6. The dried aggregates sample is allowed to passing and retained on a set of sieve.
960 234 1232 770 721 321 450 1594 1644 470 1268 508 5 906 933 954 422 167 1598 320 1053 76 630 1045 1090 1296 780 1160 370 814