Experiment Determination of Water Absorption and Density of Bricks
Experiment 3
Student Name: xxxxxx xxxxxxx
Table of Contents .................................................................................................................................... ................................................................................... ............. 3 Objective .............................................................. ....................................................................................................................................... ........................................................................ .. 3 APPARATUS ................................................................. ................................................................................................................................... ........................................................................ .. 3 DESIGNATION ............................................................. .............................................................................................................................. ........................................................................ ..... 3 SPECIFICATION ........................................................... ........................................................................................................................................ 3 PROCEDURE . ........................................................................................................................................ ..................................................................................................................................... ........................................................................ .. 4 BSERVATION ............................................................... ................................................................................................................................. 4 CALCULATIONS ..................................................................................................................................
DISCUSSIONS/OBSERVATIONS
....................................................................................................... ................................................................. ...................................... 6
................................................................................................................................... ........................................................................ .. 6 CONCLUSIONS ............................................................. .................................................................................................................................... ........................................................................ .. 7 REFERENCES: ..............................................................
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Experiment 3
Student Name: xxxxxx xxxxxxx
Objective Experiment was to calculate the density and water absorption of a sample of bricks to determine their suitability in construction. They are important factors in influencing a brick’s properties, such as the bond with the mortar, resistance to freezing and thawing, and chemical stability. They will allow us to see whether a higher density goes with a higher absorption value, and to determine the type of brick.
APPARATUS 1. Ten dry bricks 2. Two sets of 5 wet bricks 3. An electric scale 4. Transparent plastic ruler. ruler.
DESIGNATION – 1: “Specification for Clay Masonry Units” The standards referred to are BS EN 771 – 1: Units ” and Test Method: IS: 3495 (P - 2) 1992 : “water absorption” absorption ” and BS 772 – 16: 16: “Methods of Tests for Masonry Units”.
SPECIFICATION When tested the average water absorption shall not be more than 20% by weight up to class 125 and 15% by weight for higher class. PROCEDURE 1. Measure the dimensions of ten bricks using a plastic ruler to the nearest millimetre. 2. Weight each brick to the nearest gram using balance. 3. Take out the bricks from cold water and dry them with towel. 4. Weight dried bricks to the nearest gram. 5. Perform density and absorption calculations calculations
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Student Name: xxxxxx xxxxxxx
Experiment 3
BSERVATION The measured and average dimensions of the 10 dry bricks are shown below: Table 1 Dry Bricks Dimensions
Sr. No. 1 2 3 4 5 6 7 8 9 10 11 12
13 14
Number
1 2 3 4 5 6 7 8 9 10 Mean BS Value Mean Diff. Range Diff.
Length (mm) 217 213 215 214 214 215 214 213 214 213 214 215
Width (mm) 102 101 103 103 102 97 102 101 104 95 101 102
Depth (mm) 64 64 63 63 63 62 62 62 65 62 63 65
1
1
2
4
9
3
CALCULATIONS The water absorption for each of the wet bricks is shown in Table 2, calculated using the equation:
Absorption =
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Student Name: xxxxxx xxxxxxx
Experiment 3
Table 2: Weights and Absorption Absorption of 2 Sets of 5 Wet Wet Bricks
Number
1 2 3 4 5
Dry Weight (kg) 2.128 2.108 2.127 2.127 2.129
Wet Weight (kg) 2.320 2.348 2.319 2.325 2.341
6 7 8 9
2.224 2.269 2.240 2.234
2.388 2.480 2.330 2.395
10
2.237
2.354
Difference (kg) 0.192 0.24 0.192 0.198 0.212 Average = 0.164 0.211 0.090 0.161
Absorption (%) 9.0 11.4 9.0 9.3 10.0 9.7 7.4 9.3 4.0 7.2
0.117 Average =
5.2 6.6
The densities of each of the wet bricks are shown in Table 3 and were calculated using the following formula: Density =
Table 3: Weights, Dimensions and Densities of 2 sets of 5 wet Bricks
Number
1 2 3 4 5
Dry weight (kg) 2.128 2.108 2.127 2.127 2.129
6 7 8 9 10
2.224 2.269 2.240 2.234 2.237
Dimensions (m³) 0.213 × 0.100 × 0.063 0.213 × 0.100 × 0.065 0.213 × 0.100 × 0.063 0.212 × 0.100 × 0.065 0.214 × 0.100 × 0.064 Average. Density = 0.214 × 0.099 × 0.063 0.218 × 0.100 × 0.064 0.210 × 0.098 × 0.062 0.215 × 0.098 × 0.062 0.214 × 0.097 × 0.062 Average Density =
Density (kg/m³) 1586 1523 1585 1544 1554 1558 1666 1626 1756 1710 1738 1699
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Experiment 3
Student Name: xxxxxx xxxxxxx
DISCUSSIONS/OBSERVATIONS 1. The absorption results of bricks numbered 1 - 5 are relatively close together, 10 of showing a fairly uniform set of bricks. There is a larger variable in bricks 6 – 10 5.3% however; showing an inconsistent inconsistent absorption value. 2. Bricks 6 - 10 show an average density of 1699kg/m³, with an average absorption of 6.6%. Bricks 1 – 5 however show an absorption value of 9.7%, with a lower density of 1558kg/m³; illustrating that a lower absorption correlates with an increase in density. 3. In BS-3921, Engineering bricks are classed as having maximum water absorption of 7%. Bricks 6 – 10 show an average absorption of < 7%; thus are engineering bricks. Bricks numbered 1 - 5 do not fall below 7%, but are under 13.7% and are therefore common. 4. Although the widths of dry bricks number 6 and 10 are 97mm and 95mm, respectively, respectively, the bricks are in accordance with British Standards BS EN 771-1. T1 states that they are in accordance if: if: the mean of the 10 bricks falls between a minimum of 209mm and a maximum of 221mm. Furthermore, the range falls with R1 and R2, since the length does not exceed 9 and 4mm, respectively. 5. Regarding the procedure, we did not use nose callipers along the midpoint when 1 for measuring length, width and height, to comply with Standards BS EN 771 – 1 bricks less than than 250 x 125 x 100mm; instead, we relied on a plastic rule. rule. 6. Furthermore, we did not take the height of each brick from 2 points, and calculate the mean, as per the requirements of BS EN 771 – 1 1. 7. Lastly, we did not adopt the standard when measuring using a rule as specified in BS EN 722 – 16 (measuring along the centre), until prompted by the tutor. This could have resulted in inaccuracies in measurement of as much as a 2 millimetres, which would have subsequently altered the final density calculations. CONCLUSIONS From the calculations, it appears that an increase in the density of a clay brick results in a lower water absorption; this would make sense since engineering bricks are dense materials and are used in areas needed to withstand much water. 8.0 ACKNOWLEDGEMENTS
Thank you to xxxx xxxxx for reviewing this report and his subsequent suggestions.
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Experiment 3
Student Name: xxxxxx xxxxxxx
REFERENCES: 1. British Standards BS Standards BS EN 771 – 771 – 1 1 European Standard Specification Specification for Clay Masonry Units; Units; 2. British Standards BS Standards BS 772 – 772 – 16: 16: Methods of Tests for Masonry Units; 3. British Standards BS3921 Standards BS3921 Specification for Clay Bricks; 4. Test Method: IS: 3495 (P-2) 1992: Water Absorption.
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