Estimation of Masonry (Brick work)

in Construction having comprehensive knowledge about Masonry work

Brief Description

Before going to start any construction project it is fundamental requirement to calculate the material required as it helps in the reduction of cost (economize the construction). Estimation of masonry works in civil engineering construction comprises the exact calculation of bricks and binding material which is commonly mortar (cement +sand + water). This article include complete calculation of masonary work by considering example of civil Engineering Drawings and also comprehensive knowladge about the masonary work for proper understanding .

History of Masonry


Arting and crafting in the civil Engineering construction and Fabricating the infrastructures with the help of stone, clay and Brick is one of the oldest method in the construction History. The first brick in the history was sunbaked brick (more than 6000 year ago). Moving back to the history there are lot of notable structures in the world including Egyptian pyramids, the Taj Mahal and the great wall of China. Here, some examples of past historical structure like Egyptian pyramid, middle ages and present era of acmes and Skyscrapers


 

Egyptians Pyramids

As long ago ( as 2600 BC ) the Egyptian used basic masonary material to build one of the most creative structure in the history. By the help of limestone, they created pyramid by stacking the stones. For the walls and roofs of burial chamber of pyramid, Granite was used. For sustaining the strucrure they used gypsum and Rubber although, these materials were not pocessed more binding properties.

 


 

The middle Era

In  the middle ages the stones were used for the construction of bridges, castels and other structure just to check the sustainability and durability of structures. The outcoems were favourable as stone caused the opportunity for handy and masons to build heavier and highrise superstructure .

 

 


 

Era of Acme’s and Skyscrapers:

 In the late 19th century the art of masonry has been replaced with metal frames in high rise infrastructures. However, in the construction of houses Bricks are commonly used. As the concrete is being frequently used in present era so particularly in skyscrapers and acmes, masonry work is replacing with concrete blocks and steel structural members as it has more compressive strength and durability.

 

Before estimation of masonry work here are some basic terminologies and knowledge which is necessary to comprehend for Civil Engineers

Terminologies and their Description

Masonry construction comprises the masonry units like brick, concrete blocks, natural and manmade stone. These units are laid or bind by using commonly used binding mixture “mortar” (cement sand and water)

Bricks:

          Brick is a small rectangular block usually made of fired and sun-dried clay. Now a day mostly kiln is used in the manufacturing of bricks. It is major component in masonry construction

Standard sizes of Brick:

            The standard dimensions are considered

There are usually two standard system of Units used in the world SI (metric) system and FPS system (inches)

SI UNITS

FPS UNITS

Different countries have different standards of size. Further details of sizes can be checked through  this link https://www.google.com/search?q=standard+size+of+brick+&tbm

Classification of Bricks (Based On Quality)

First Class brick:

            The size of first class brick is standard. It has yellowish and reddish color. Well burnt and have smooth edges. The absorption capacity of moisture is usually 10 percent. It has crushing strength 245kg/cm2. When such type of brick struck with each other or with hammer it produces a metallic sound. For long durability first class bricks are used in construction.

Second Class brick:

            It has also standard size but color is yellow and red (uniform). Usually it is well burnt but sometime there is slightly over burnt. It has absorption capacity more than 10%. Crushing strength is usually lesser than first class brick (154 kg/cm2). It is generally used construction of single story building.

Third Class brick:

            It has not regular and definite shape. It has light red color. It is usually under burnt and texture of third class brick is not uniform. The absorption capacity is usually higher ( 15% to 20%). It has lower strength (105 kg/cm2). It produces very dull sound when struck it with each other

Mortar

Mortar is the mixture of cement sand and water. it can have different proportion usually in brick masonry work (1: 4) and while during calculation of volume of mortar usually 15 to 20 % of total volume of brick will be considered and remaining volume (80% to 85%) will be considered for calculation of bricks

 

Let’s take example of house plan and calculate the number of bricks and quantity of mortar in the masonry work during the construction.

Brick work in foundation

The cross sections 4.5” and 9” wall are mentioned below

9” wall cross section

4.5” wall cross section

Center line Method for estimation of Building

In this method total length of wall which has same thickness will be added. The total length will be same for calculation of excavation, P.C.C and brick work in foundation. For corner and junction special attention is required

Usually there are 4 type of wall junction in a building

Brick work in Super structure

Case (i) 9” thick wall meet 9” thick wall:-

In this case the total deduction from t1

made in center line is

Correction = – 1/ 2(t1) N1

Case(ii) 41/2” thick wall meet 9” thick wall: -

In this case the total deduction from t2

made in center line is

Correction = – 1/ 2(t1) N2

Case (iii) 9” thick wall meets 41/2” thick wall: -

In this case the total deduction from t1

made in center line is

Correction = – 1/ 2(t2) N3

Case (iv) 41/2” thick wall meets 41/2” thick wall: -

In this case the total deduction from t2

made in center line is

Correction = – 1/ 2(t2) N4

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

Total Center line (9”) = 13’ + 6’ + 13’ + 11’ + 5.5’ + 10’ + 6.5’ +

  10’ + 6.5’ + 5.5’ + 13’ + 11’ + 19’ + 13.33’ + 13’ + 11’ + 6’ + 6’ +

  (9” + 4.5” + 9” + 9” + 9” + 9” + 9” + 9” + 9” + 9” + 9” + 9” + 9”

   + 4.5”) = 189.08’

 Total Center Line (4.5”) = 4.25’ + 6’ + 9” = 11.25’

Junction correction: –

9” Wall = 189.08’ – ½ (thickness of 9” at same level) 9 – ½ (thickness of 4.5” at same level) 2

9” Wall = 189.08’ – ½ (0.75) 9 – ½ (0.375) 2 = 185.52’

4.5” Wall = 11.25’ – ½ (thickness of 9” at same level)

4.5” Wall = 11.25’ – ½ (thickness of 9” at same level) = 10.875’

Brick work in foundation

Brick work in Super structure:

Total volume of masonry work:

511.45+1394.875= 1906.325 cubic feet

As

80% of total volume is (pure brick work) = 1525.06 cubic feet

20% of total volume (mortar)= 381.265 cubic feet

Volume of one brick in cubic feet= 0.0703125 cubic feet

Total number of bricks= total volume of bricks / volume of one brick

                                      = 1525.06 / 0.0703125

                                =21689 (total number of Bricks)

Wet Volume of mortar = 381.265 cubic feet= 10.804 cubic meter

Mix ratio 1:4

 Dry volume of mortar= wet volume * 1.33

                                    = 10.80 * 1.33 =14.370

Quantity of cement = (Dry Volume of mortar* cement ratio)/ sum of the ratio

                                = (14.37*1) / (1+4) = 2.87 m3

Density of cement= 1440 kg/ m3

Mass of cement= density * volume =   2.87* 1440 = 4132.8 kg

Mass of one cement bag = 50 kg

Total number of bags = total mass of cement / mass of one bag

                                    = 4132.8/ 50 = 82.6 = 83 bags approx.

Quantity of sand =quantity of cement * 4

                          = 2.87 *4 = 11.48 m3 = 405.4 ft3

Quantity of water

Water cement ratio = weight of water/ weight of cement

Usually w/ c = 0.5

Weight of water = 4132.8* 0.5= 2055.4 kg (liter)

Conclusion

From above estimation of masonry work in any civil Engineering work it can be concluded that the calculations are very simple and easy to comprehend. The only focus should be on the corners and junctions of wall as there is usually deduction of volume from those juxtapose positions. Apart from this, number of doors, windows and even lintel (above the door) should be deducted while during the calculation of masonry work, it causes the overall reduction in cost.

Follow us

All Posts

Reviews

3D Studio Max

Projects

+ Building Works

+ Infra Structure

+ Surface Drainage System

+ Roads & Highways

+ High Rise Buildings & Towers

+ Water Supply & Sewerage System

+ Pipeline Construction