Lab Report U4 (Density)

Faculty

Civil and Environmental Engineering Engineer ing

:

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

TEST 1: DENSITY OF A BRICK

1.0

INTRODUCTION

1.1 Bricks are blocks of ceramic usually laid using various kinds of mortar. Bricks have to be tested to meet certain standards before used to lay for for masonry. masonry. Among the qualities tested were density, water absorption and compressive strength of brick

1.2 Density of a brick was depending depend ing on clay composition. Density of a brick var ies from 2250 to 2800/3 . A brick varies from 1.8 kg k g to 3.8 kg in weight. To calculate the density of a brick, the formula that being used is ;1

 =    = Where

   =  =

 

Density

m = Mass V = Volume

2.0

OBJECTIVE

2.1

3.0

To determine the density of brick according to Malaysia standard

EQUIPMENT AND MATERIAL

3.1

EQUIPMENT i) ii) iii)

1

Vernier caliper

3.2

MATERIAL i)

Brick Sample

Steel ruler Balancer (6kg x 0.1g)

OXFORD FAJAR, POH LIONG YONG ,S.NAGAPPAN - PHYSICS FOR MATRICULATION,

Page | 1

Faculty

4.0

Civil and Environmental Engineering

:

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

PROCEDURE

1.

The dimension of brick was measured by using a vernier caliper and steel ruler and the volume of brick was calculated.

2.

The mass of brick was determined by using weighing machine.

3.

The density of brick was calculated by using the formula.    = Where

   =

 

density

m = Mass V = Volume

Page | 2

Faculty

5.0

Civil and Environmental Engineering

:

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

RESULT Test/Brick Volume of Brick, m

3

1

2

0.09995 x 0.21 x 0.0709 =

0.09086 x 0.215 x0.07026=

0.0014882

0.0013725

2.614

2.459

2.614/0.0014882 =

2.459/0.0013725 =

1756.5

1791.6

Mass of Brick, kg Density, kg/m

3

3

Average Density , kg/m  

6.0

1774.1

ANALYSIS OF DATA

1. The result shown that there are differences between brick 1 and 2. 2. Brick mass of brick 2 is higher than brick 1. 3. The brick mass will affected the density of brick.

7.0

PRECAUTIONS

1. For accurate readings of width and height of the brick, vernier caliper is being used. 2. Initial reading of vernier caliper must be zero before it is used for measurement. 3. Vernier caliper should be perpendicular to the object which be tested so that we can get a correct and accurate result. 4. The balance beam surface should be clean and clear so that we can obtain a accurate result about the brick mass

Page | 3

Faculty

8.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

DISCUSSION

1. Different brick will have a different number of densities. 2. The density of a brick is depends on its mass and volume. The higher t he mass the higher the density. Meanwhile, the higher the volume, the lower its density. 3. In other words, volume of brick is inversely proportional to the density of brick and mass of brick is directly proportional to the density of brick.

9.0

CONCLUSION 3

The average density of the bricks sample according to Malaysia Standard is 1774.1 kg/m

Page | 4

Faculty

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

TEST 2: WATER ABSORPTION

1.0

INTRODUCTION

There are many factors that will affect the water absorption of a brick. Water absorption depends on the clay composition, as well as duration and temperature of the firing process. By using the 2

formula below, the percentage of water absorption can be calculated.

 Percentage of water absorption, % =

2.0

X 100%

To determine water absorption of brick accord ing to Malaysia standard.

EQUIPTMENT AND MATERIAL

3.1

EQUIPMENT

i)

2

   

OBJECTIVE

2.1

3.0

        −   

Balancer (6kg x 0.1g)

3.2

MATERIAL

i)

Brick sample

http://www.ptli.com/testlopedia/tests/water_absorption-d570.asp

Page | 5

Faculty

4.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

PROCEDURE

1.

The mass of dried brick sample was determined by weighing it with balance.

2.

The brick sample was immersed in water for half hour.

3.

The mass of wet brick was determined and percentage of water absorption for that brick sample was calculated by using formula.

 Percentage of water absorption, % =

5.0

        −       

X 100%

RESULT Brick Sample

1

2

Dried mass, kg

2.614

2.459

Mass after immersed, kg

2.987

2.858

2.987−2.614

Percentage of water absorption, %

2.614

  100%=

14.27 Average percentage of water absorption, %

2.858 −2.459 2.459

  100% =

16.23 15.25

Page | 6

Faculty

6.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

ANALYSIS OF DATA

1. Mass of brick after immersed will be much higher co mpare to its original mass. 2. Formula that being used will calculate the percentage of water that being absorbed by the brick specimen. 3. Mass of dried mass of brick is inversely proportional to density of brick. 4. When the mass of brick is greater, the percentage of water absorption for the brick is lower.

7.0

PRECAUTIONS

1. After 30 minutes being immersed in the water, the brick sho uld be taken out of the water and held in the air until the dripping stops so as to accurately calculate the water absorbed by the brick. 2. Both of the brick samples are fully submerged in water for the same time. 3. The bricks are being wiped before being weight to avoid the beam to calculate the weight of the water.

8.0

DISCUSSION

1. The absorption of bricks is defined as the increase in the weight of brick due to water. Water absorption greatly affects the durability of brick. 2. A good brick should have sharp edges and angle. Good, hard bricks may absorb less than 10  percent water. 3. The heavier brick is denser, which the density would be higher. So, higher density brick will has less space in the brick structure. Fewer spaces will co ntribute to less water can be absorbed. 4. High rate of water absorption of a specimen may cause swelling of stabilized clay fraction and resulting in losing strength with time.

3

3

http://www.insipub.com/ajbas/2011/September-2011/6-12.pdf

Page | 7

Faculty

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

5. When the brick is dry, water is rapidly sucked out of the mortar preventing goo d adhesion and  proper hydration of the cement and when the brick is very wet the mortars tends to float on the 4

surface without gaining proper adhesion .

9.0

CONCLUSION

The average percentage of water absorption of brick according to Malaysia Standard is 15.25%.

4

Oti, 2009; Walker, 1999

Page | 8

Faculty

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

TEST 3: COMPRESSIVE STRENGTH

1.0

INTRODUCTION

Compressive strength decreases with increasing porosity and is influenced by clay composition and firing process. Compressive strength of brick is limited by brittle fracture and sensitive to flaws associated to large particles, fissures formed during shaping, and shrinkage crack.

2.0

OBJECTIVE

2.1

3.0

To determine the compressive strength of a brick according to Malaysia standard

EQUIPMENT AND MATERIAL

3.1

Equipment

i) Vernier caliper

3.2

Material

i) Brick sample

ii) Steel ruler iii) Balance (6kg x 0.1g) iv) Compressive machine (ELE Compact-1500)

Page | 9

Faculty

4.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

PROCEDURE

i.

The dimension of the brick was measured by using vernier caliper and steel ruler.

ii.

The top area and the volume of the brick sample were calculated.

iii.

The mass of brick sample was determined by using weighing machine.

iv.

The brick was put into compressive machine and the controller was twisted until the brick fail

v.

The average of compressive strength for brick sample was calculated. Page | 10

Faculty

5.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

RESULT

TEST SAMPLE

1

2

Area of the brick sample, m

0.09935 x 0.214 =

0.09918 x 0.021 =

0.00213

0.00208

Volume of the brick sample, m

0.09935 x 0.214 x 0.0707 0.09918 x 0.021 x 0.07139 = 0.001503

= 0.001486

Mass of brick, kg

2.618

Density (  ), kg/3

1741.85

1743.61

Maximum value of load, kN

422.320

317.271

422.320   1000 0.00213   1 000 000

Value of compressive strength, N/2

Average of compressive strength N/2

2.591

317.271  1000

=

0.00208   1 000 000

198.27

=

152.53 175.4

Page | 11

Faculty

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

Brick 1

Brick 2

Page | 12

Faculty

6.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

ANALYSIS OF DATA

1.

The brick is denser, it can resist more load.

2.

The value of maximum load resist by the brick is directly proportional to compressive strength of the brick.

7.0

PRECAUTIONS

1.

Brick which was tested for compressive strength failed as it cracked prematurely. The reason being that the surface of the brick was u neven, thus uneven distribution of compressive force caused it to crack at a below average load. Once the compressive testing machine detected the crack it immediately ended the testing and the results were a failure.

2.

When the compressive machine is activated, everyone should stand a distance from the machine to avoid injury from the flying debris.

3.

Once the compressive test is complete, the surface of the t esting machine should be cleared of all debris so that it will not interfere with future tests.

8.0

DISSCUSSION.

1.

Avoid from using any cracked bricks to prevent from any errors.

2.

The peak value of the load during compression should be recorded before the value fall down because of the brick fail.

3.

Make sure the surface of the plate is cleaned before start the compression.

4.

The denser bricks will have compact component and fewer spaces between particles. So, it need more load to compress it to fail condition and the compressive strength would be higher.

5. The formula to calculate compressive strength is ;

5

Uniaxial Compressive Strength = Force / Area 5

http://wiki.answers.com/Q/Formula_for_calculating_compressive_strength_of_cylindrical_body_of_concrete

Page | 13

Faculty

9.0

:

Civil and Environmental Engineering

Department :

Structure and Materials Engineering

Title

Density, Water Absorption and Compressive Strength of Bricks

:

CONCLUSION

A good brick can have an ultimate compressive strength as low as 11MPa and some brick can 6

exceed 104MPa.

6

 Chapter 4; Brick and Masonry, 1 st Ed, Civil Engineering Materials

Page | 14