DCC3113 DETERMINATION OF AGGREGATE IMPACT VALUE.
- 1. 1 CIVIL ENGINEERING DEPARMENT DCC 3122 HIGHWAY LAB REPORT TITLE DETERMINATION OD AGGREGATE IMPACT VALUE COURSE / SESSION DCC 3122 – GEOTECHNIC AND HIGHWAY LABORATORY PREPARE BY GROUP GROUP A GROUP MEMBERS 1. AINUNYASMINE BINTI HASLAN 03DKA16F2023 2. MOHD IQBAL NAQIUDDIN BIN ZULKIPLI 03DKA16F2018 3. MOHAMAD AMIR SAIF BIN ABDUL HAMID 03DKA16F1130 4. MUHAMMAD AIZAT BIN ABD RASHID 03DKA16F2021 LECTURER’S NAME 1. PUAN SALMA BINTI YAHYA 2. EN. AHMAD TAZRI BIN AZIZ 3. CIK FAIZAH BINTI HJ. ZAINAL ABIDIN PRACTICAL DATE DECEMBER 5, 2017 SUBMISSION DATE DECEMBER 12, 2017
- 2. 2 Table of Contents OBJECTIVES .................................................................................................................................1 THEORY .......................................................................................................................................2 APPARATUS .................................................................................................................................3 PROCEDURE..................................................................................................................................4 RESULT / DATA ...........................................................................................................................6 CALCULATIONS ..........................................................................................................................6 DISCUSSION ..................................................................................................................................7 PRECAUTIONS..............................................................................................................................8 CONCLUSION................................................................................................................................9 REFFERENCES ............................................................................................................................ 10
- 3. 3 OBJECTIVES To assess their suitability inroad construction on the basis of impact value. This test is done to determine the aggregate impact value of coarse aggregates. Many tests have been developed toempirically characterize aggregate properties without, necessarily, strong relationships to the performance of final products incorporating an aggregate. This seems to be particularly true for aggregate “toughness and abrasion resistance” and “durability and soundness.” The objective of this research is to select tests for characterizing aggregate toughness/abrasion resistance and durability/soundness that are related to the performance of asphalt concrete pavements.
- 4. 4 THEORY The property of a material to resist impact is known as toughness. Due to movement of vehicles on the road the aggregates are subjected to impact resulting in their breaking down into smaller pieces. The aggregates should therefore have sufficient toughness to resist their disintegration due to impact. This characteristic is measured by impact value test. 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. Aggregate Impact Value (AIV) is the percentage of fines produced from the aggregate sample after subjecting it to a standard amount of impact. The standard amount of impact is produced by a known weight, i.e. a steel cylinder, falling a set height, a prescribed number of times, onto an amount of aggregate of standard size and weight retained in a mould. Aggregate Impact Values, (AIV’s), below 10 are regarded as strong, and AIV’s above 35 would normally be regarded as too weak for use in road surfaces. Aggregate Impact Values and Aggregate Crushing Values are often numerically very similar, and indicate similar aggregate strength properties. Classification of aggregates using Aggregate Impact Value is as given below: Aggregate Impact Value Classification <20%.= Exceptionally Strong 10 – 20% .=Strong 20-30%. =Satisfactory for road surfacing >35%.= Weak for road surfacing
- 5. 5 APPARATUS 1. Aggregate Impact Value Test Machine 2. BS test sieve 3. A metal tamping rod 4. A weighing Balance 5. Aggreagate
- 6. 6 PROCEDURE The test sample was prepared as follows: 1. The sample was sieve through test sieves and then the material passing through the sieve and that retained on the sieve was collected. 2. The cylindrical mould was measure and it weight recorded as W1. 3. The cylindrical mould was then fill in measure layers and then each layers was tamper with 25 blows using the tamping rod. Each blow was given by allowing the Tamping rod to fall freely from a height of about 50mm above the Surface of the Aggregate, evenly distributed over the surface. 4. The net mass of Aggregate was then measure and recorded as W2. 5. The steel cup (which is part of the test machine) was fixed firmly in position on the base of the machine. 6. The height of the hammer was adjusted so that its lower face is 380mm above the upper surface of the Aggregate and the allow it to fall freely To the Aggregate. 7. The Aggregate was subjected to a total of 15 such blows, each being delivered at an interval of not less than one second. 8. The crushed Aggregate was then removed and was pass through a sieve size 2.36mm.
- 7. 7 9. The fraction passing the sieve size 2.36 was measured and the weight was recorded as B. The weighed of the fraction retained was also measured and the weight recorded as C.
- 8. 8 RESULT / DATA S1 S2 Total weight of dry sample (W1) 560.5g 463.7g Weight of portion 2.36mm sieve. (W2) 95.1g 71g Aggregate impact value (%) 17% 15% CALCULATION Sample 1 1. Total weight of dry sample (W1) : 3255.7 g – 2695.2 g = 560.6 g 2. Weight of portion passing 2.36 mm sieve (W2) : 582.7 g – 487.6 g = 95.1 g 3. Aggregate impact vaue : 95.1 560.5 × 100 = 17 % Sample 2 1. Total weight of dry sample (W1) : 3154 g – 2690 g = 463.7 g 2. Weight of portion passing 2.36 mm sieve (W2) : 558.4 g 487.4 g = 71 g 3. Aggregate impact vaue : 71 463.7 × 100 = 15 %
- 9. 9 DISCUSSION After 15 blows from the hammer, the crush sample was reduced to smaller sizes. The proportion of material passing sieve size 2.36mm was smaller than that retained. The aggregate impact value indicates a relative measure of the resistance of the aggregate to a sudden shock or impact which in some aggregates differs from its resistance to a slow compressive load. From the calculations done we know that the aggregate can be acceptable as their Aggregate Impact value is less then 20% Aggregate Impact Value
- 10. 10 PRECAUTIONS 1. To wear safety shoes & goggles at the time of testing. 2. Before testing, machine should be properly checked. 3. After test clean the sieve by a smooth brush. 4. Keep all the exposed metal parts greased. 5. Keep the guide rods firmly fixed to the base & top plate. 6. Equipment should be clean thoroughly before testing & after testing. 7. Special care should be taken that no outer air enters when using the balance.
- 11. 11 CONCLUSION From the experiment, we get the value is 17% and 15%less than the requirement of JKR’s; 20%.Aggregate physical property must lower Aggregate Impact Value, AIV because is tougher and resistance to crushed. We can conclude that the aggregate been used are medium toughand resistant to be crash. It’s because the value are more than half than JKR’s requirement.These experiments are successful because its still not exceed the JKR’s requirement.
- 12. 12 REFERENCES 1. Transportation laboratory manual, civil engineering department, university of Ilorin. 2. org/building/building-material/determination-of-aggregateimpact-value/1355/ 3. engineeringcivil.com/aggregate-impact-value.html 4. org/2013/05/07/aggregate-impact-value-is2386-part-iv-1963/ 5. com/plain-reinforced-concrete-experiments/exp-4-aggregateimpact-value/