The use of mineral aggregates is related to the increasing demand in construction, railway and road infrastructures. However, mineral aggregates can appear to be of variable quality, directly affecting their suitability for respective earthwork applications. Since the production of mineral aggregates should ensure the standardized, high-quality …
on requirement and Gradation of Aggregate). Fig. 3: Thickness Gauge- For Flakiness Index Thickness Gauge have width equal to 0.6 times the mean dimension of the aggregate. Fig. 4: Length Gauge- For Elongation Index Length Gauge have length equal to 1.8 times the mean dimension of the aggregate.
Aggregate Crushing Value Apparatus. The apparatus for Aggregate Crushing Value Test comprises the following: Fig 1: Aggregate Crushing Value Apparatus. A steel cylinder with a 15 cm diameter, equipped with a plunger and base plate. A straight metal tamping rod with a diameter of 16 mm and a length of 45 to 60 cm, …
Crushed aggregate tests, like the flakiness and elongation index, assess particle shape and size, which influence workability and strength. ... Aggregate crushing test is a standard method of measuring the strength of coarse aggregates used in concrete. The test involves applying a gradually increasing compressive load to a sample of …
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 …
Determinations for the flakiness index and flakiness and elongation of aggregate use a British Standard classification system consisting of a Thickness Gauge for determining flakiness index and a metal Length Gauge for determining elongation index. Aggregate is separated into seven sieve fractions from 63—6.3mm and each fraction is evaluated ...
Aggregates are considered the main components of asphalt mixtures in terms of weight, volume, and flexibility of pavements. Countries are looking for alternative materials for use in pavements as ...
The average aggregate crushing value (ACV) and the aggregate impact value (AIV) obtained from the evaluations is 28.7% and 29.5% respectively and are within the acceptable standard limits. The specific gravity and water absorption gave average values of 2.60 and 0.22% respectively while the flakiness index obtained from the analysis is …
This method is based on the classification of aggregate particles as flaky when they have a thickness (smallest dimension) of less than 0.6 of their nominal size, this size being …
Nevertheless, a higher flakiness index was obtained after the crushing of non-flaky particles and a lower one after the crushing of flaky particles. The flakiness index for grains below 16 mm ...
The Flakiness index of aggregates is the percentage by weight of particles whose least dimension (thickness) is less than three- fifths (0.6times) of their mean dimension. This …
Nevertheless, a higher flakiness index was obtained after the crushing of non-flaky particles and a lower one after the crushing of flaky particles. The flakiness index for grains below 16 mm ...
A low aggregate crushing value indicates high crushing strength of aggregates. 3. Aggregates having elongation index values not greater than 15% are generally considered suitable for pavement construction. ... Flakiness index is the percentage of the weight of aggregates whose least dimension (thickness) is less than …
Flakiness Index of aggregate is the percentage by weight of aggregate particles whose least dimension is less than 0.6 of their mean dimensions. This test is applicable to aggregates having size larger than 6.3mm.
It is generally accepted that the mechanical properties of an aggregate are improved from each crushing stage because weak minerals are worn off. Hence, there is a risk of overrating the quality of an aggregate when the tested samples are laboratory crushed twice after primary crushing. ... An empirical model for predicting flakiness in …
The 'flakiness' of an aggregate is measured as the weight proportion passing a specially designed slotted sieve. A limit of 35% flaky particles is imposed for general purpose …
The shape test assesses the flakiness and elongation index, ensuring that aggregates do not contain particles detrimental to the mix's stability. 6. Bitumen Adhesion. Bitumen Adhesion Test on Aggregates: ... After crushing, the aggregate is sieved through a 2.36mm sieve, and the weight of the material passing through is measured. The ...
Aggregates used in road construction, should be strong enough to resist crushing under traffic wheel loads. If the aggregates are weak, the stability of pavement structure is …
Several tables of results are included. One purpose of the paper is to open a discussion of whether flakiness index values could be raised at par to concrete, without disturbing other physical requirements of aggregate against wet mix macadam construction. Availability: Find a library where document is available.
Flakiness, one of the shape characteristics of aggregate, is a problematic property associated with concrete behaviour (1,2,4,(10)(11)(12). ... Effect of flakiness of coarse aggregate on concrete ...
AIM OF THE EXPERIMENT: To determine the Flakiness Index of the given sample of course aggregate. CODE OF REFERENCE: • IS 2386(Part 1):1963 Methods of Test for Aggregates of Concrete- Particle Size and Shape. Reaffirmed Dec 2016 • ASTM 4791-10: Standard Test Method for Flat Particles, Elongated Particles or Flat Elongated Particles …
Quality estimation of rock aggregate raw materials is often performed with mechanical tests on aggregates crushed with laboratory crushers. However, standardised mechanical tests are intended for testing products, not raw materials. Different laboratory crushers produce aggregates with varying shape properties [flakiness index (FI), shape …
What is the Flakiness Index, and why is it important in road construction? The Flakiness Index measures the proportion of flat and elongated particles in an aggregate. It's important in road construction because flaky particles can easily break down when subjected to loads along their thin axis, leading to pavement failure.
Explore the Flakiness and Elongation Index test conducted on coarse aggregate to assess its particle shape and size distribution. Dive into the details of the Flakiness Index and …
The Flakiness Index test determines the percentage by weight of aggregate particles whose least dimension is less than 0.6 of their mean dimension. This test is applicable only to coarse aggregates. To calculate the flakiness index of a sample, the weight of each fraction of aggregates passing and retaining on specified sieves is …
Aggregate crushing value = (W2 x 100) / (W1-W) W2 =Weight of fraction passing through the appropriate sieve W1-W =Weight of surface dry sample. The mean of two result to nearest whole number is the aggregate crushing value. Result The aggregate crushing value of the given sample= Aggregate Crushing Values for Roads and Pavement …
This paper accounts for a closely controlled experimental program aimed at clarifying the variation of aggregate shape with two parameters, gyratory crusher …
The 'flakiness' of an aggregate is measured as the weight proportion passing a specially designed slotted sieve. ... (ACV) – this is the measurement of the resistance of aggregate to crushing by compressive force. A test specimen (10-14mm) is compressed (up to 400 kN) and the proportion of material passing 2.36 mm is the ACV (mean value ...
The new standard mainly used for determining the shape of aggregate is the SS-EN 933-3, and includes the flakiness index FI. By comparing the output of the crusher to different standards, it is possible to keep track of the quality of the produced aggregate. The flakiness index refers to the percentage of flaky particles.
Concept and significance of the Aggregate crushing value test. The ' aggregate crushing value test ` gives a relative measure of the resistance of an aggregate to crushing under a gradually applied compressive load. Aggregate crushing value is defined as the percentage by weight of the crushed (or finer) material obtained when the …
