Compression and Flexure Test of Concrete LAB REPORT 2020

2. Sieve Analysis of Aggregates 2.1 Objective 1. To determine the grading of the aggregates by sieving the concrete looking for percentage passing of different sizes of sieve. 2. To determine the workability by compa ...

2. Sieve Analysis of Aggregates 2.1 Objective 1. To determine the grading of the aggregates by sieving the concrete looking for percentage passing of different sizes of sieve. 2. To determine the workability by comparing the result with the British Standard limit (B.S. 1881) 3. To consturct the grading curve of the mixed aggregates 2.2 Apparatus and materials Apparatus: 1. Sieving machines 2. Test sieves 3. Electronic Balance Materials: 1. Fine Aggregates – Crushed Granite rocks with a theoretical maximum size of 5mm 2. Coarse Aggregates – 10mm size aggregates and 20mm size aggregates made of granite rocks 2.3 Procedure 1. 5kg of 20mm aggregate is first weighted then is placed into the sieving machine with different sieve sizes of sieve plates arranged in order according to the British Standard. The sieve plates should be arranged as follow from the top to the bottom: 25mm, 20mm, 10mm, and 5mm. The sieving machine is then turned on. After the machine stops, aggregate retained on each sieve will then be weighted accordingly and recorded. 2. After clear all the aggregate in the sieves, Step 1 is repeated with 2kg of 10mm aggregate using the same set of sieve. 3. 0.5 kg fine aggregates will be sieved using another sieving machine with sieve plates arranged as follow from the top to the bottom: 5mm, 2.36mm, 1.18mm, 600μm, 300μm and 150μm. The sieving machine is then turned on. After the machine stops, aggregate retained on each sieve will then be weighted accordingly and recorded 4. The percentage passing each sieve of the 3 sizes of aggregates is calculated for the plotting of a grading curve.4 5. The grading curve of the combined aggregate will then be deduce. The mixing ration of 20mm aggregate:10mm aggregate:fine aggregate is 2:1:1.5.5 15 2.4 Result 20 mm Aggregates (Total Weight of Sample=5000g) B.S. Weight Retained (g) Weight Passing (g) Percentage Passing (%) B.S. Limits Sieve 25mm 0 4999.4 100 100% 20mm 262.1 4737.9 94.77 85%-100% 10mm 4613 124.9 2.50 0%-25% 5mm 122.9 1.4 0.028 0%-5% Residue 1.4 0 0 -- Total 4999.4 Max. Aggregate Size: 20 mm Particle Size Distribution of 20mm aggregates 120 100 80 Percentage passing (%) 60 40 20 0 0 5 10 20 25 30 Sieve size (mm)