Apparatus the apparatus consists of an impact testing machine, a cylindrical measure, tamping rod, is sieve, balance, tamping rod and oven. Adjust the height of the hammer so that its lower face is 380 mm plus or. Testing coarse aggregates for resistance to impact aggregates. The characteristics of aggregates impact performance of fresh and hardened. This test is done to determine the aggregate impact value of coarse aggregates. The test sample shall consist of aggregates the whole of which passes through.
The impact test bs 812112, 1990, as in the case of the compaction test bs 812110, 1990, has been taken out of the set of standard tests used for determining the physical properties of aggregates for assessing their suitability for use in construction applications. Pdf gradation of aggregates and its effects on properties. Experiment findings pdf available february 2018 with 8,362 reads how we measure reads a read is counted each time someone views a. The crushed aggregate is removed from the test specimen and sieve it through the 2. Posts about aggregate impact value test pdf download written by kishan mudavath. The sample used for this test shall be taken in accordance with chapter 2. The aggregate impact value is a measure of resistance to sudden impact or shock, which may differ from its resistance to gradually applied compressive load.
The aggregate comprising the test sample shall be dried in an oven for a period of four hours at a temperature of 100110 c and cooled. The aggregate impact value gives a relative measure of the resistance of an aggregate to sudden shock or impact, which in some aggregates differs from its resistance to a slow compression load. Improper use of test procedures can result in inaccurate data and mistaken conclusions about aggregate and concrete quality. This standard is issued under the fixed designation c6c6m. Resistance of the aggregates to impact is termed as toughness. Some indot contracts specify type ap aggregates for use in specific applications of portland cement concrete. More performance tests are also used to test aggregates in concrete.
Fill the cylinder with aggregate in 3 layers, 25 strokes of tamping for each layer. Aggregates for the test sample can be decided by passing it through 12. A typical consensus specification for fine and coarse aggregate for concrete is astm c 33. To find impact value of the given aggregate sample. Class ap is the highest class and is assigned to aggregates which m eet the requirements for all indot uses.
The net weight of the aggregates in the measure should be determined to the nearest gram weight a. The apparatus of the aggregate impact value test as per is. Synthetic aggregates may be either byproducts of an industrial process, in the case of blastfurnace slag, or products of processes developed to manufacture aggregates with special. Impact value of aggregate will give aggregate capability against sudden loads or forces. Jan 23, 2018 aggregate impact value test determines the aggregate impact value aiv of aggregates which provides a relative measure of the resistance of an aggregate to sudden shock or impact. Free software downloads we have just added a free download for our bm239 marshall test software. Uta0650 aggregate impact value aiv testing apparatus. Aggregates impact civil engineering materials testing. Mar 15, 2017 to ditermine the toughness of the aggregate by impact test for the love of physics walter lewin may 16, 2011 duration. The cup shall be fixed firmly in position on the base of the machine and the whole of the test sample placed in it and compacted by a single tamping of 25 strokes of the tamping rod. Jan 23, 2018 posts about aggregate impact value test pdf download written by kishan mudavath. Objective for determination of the aggregate impact value of coarse aggregate, which passes 12.
This test is done to determine the aggregate impact value of coarse aggregates as per is. Aiv test is conducted to determine the aggregate impact value of coarse aggregate. The aggregates should therefore have sufficient toughness to resist their disintegration due to impact. Aggregates impact impact test equipment ltd home page. Determination of aggregate impact value impact test on aggregates. Pdf standard test method for sieve analysis of fine and. The resistance of the material to failure by impact is known as toughness. The apparatus used for determining aggregate impact value of coarse aggregates is impact testing machine conforming to is.
What do you understand by dry and wet impact value. Dec 29, 2014 a test designed to evaluate the toughness of stones i. Aggregate impact value test construction aggregate. The strength of aggregates do not contribute to the strength of concrete for low strength concrete. Method of test for determining aggregate impact value of soft coarse aggregates ced 6. Procedure to determine aggregate impact value i the cup of the impact testing machine should be fixed firmly in position on the base of the machine and the whole of the test sample placed in it and compacted by 25 strokes of the tamping rod. Aggregate impact value testing aiv test civil engineering. The vertical axis named x k is the dop mm caused by the unit crosssection kinetic energy of projectile, and can be calculated as. Aggregate impact value aiv test machine mechanical and. Aggregates used in the pavement should be able to resist the effect caused by the jumping of the steel. The impact machine shall rest without wedging or packing upon the level plate, block or floor, so that it is rigid and the hammer guide columns are vertical. Aggregate classification astm c125 significance of test apparatus procedure calculations results designation number.
An impact value is measured as % of aggregates passed through the 2. Test specimens, testing conditions, mechanical testing, test equipment, specimen preparation, cement and concrete technology, reproducibility, aggregates, impact testing. Determination of aggregate impact value impact test on. Aggregate impact value the value of aggregate impact test w1w2100.
The pendulum shaft is connected in the antifriction bearings. Introduction on aggregate impact testing machine ppt. For assessment of toughness property of aggregates for the concrete construction tools and equipment impact testing machine description of machine pendulum impact testing machine basically comprises of the strong frame structure, the sample sustenance along with the measuring and computing dial. The test sample shall consist of aggregate the whole of which passes a 12. The machine consists of a metal base with a plane lower surface supported well on a firm floor, without rocking. The sieved aggregates should be dried in an oven and then filled in a cylindrical steel cup and tamped with 25 strokes by temping rod. Gradation of aggregates and its effects on properties of concrete. Aggregates aggregates generally occupy 65 80% of a concretes volume. This characteristic is measured by impact value test. The measuring cup shall be filled about onethird with the.
Methods of test for aggregates for concrete, part 4. To determine the aggregate impact value of coarse aggregates as per is. Coarse aggregates are divided into classes based on quality requirements as noted in the classification of aggregates table. Aggregate impact value of material a is 15 and that of b is 35. The aggregate impact value testing apparatus, meets with bs 812, it is robustly designed to determine the aggregate impact value aiv of aggregates which provides a relative measure of the resistance of an aggregate to sudden shock or impact. Impact test the aggregate impact test is carried out to evaluate the resistance to impact of aggregates.
The fine and coarse aggregates generally occupy 60% to 75% of the concrete volume 70% to 85% by mass and strongly influence the concretes freshly mixed and hardened properties, mixture proportions, and economy. The aggregate impact value testing apparatus is robustly designed to determine the aggregate impact value aiv of aggregates which provides a relative measure of the resistance of an aggregate to sudden shock or impact. Aggregates are inert fillers floating in the cement paste matrix for concretes of low strength. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Aggregate impact and crushing test linkedin slideshare. This degree is assessed by a sieving test on the impacted specimen and is taken as the aggregate impact value. Test aggregates are filled up to about onethird full in the cylindrical measure and tamped 25 times with rounded end of the tamping rod.
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