Table of Contents
Brickwork:
Brickwork is common building work. In which bricks are used for construction work.
Note that upto 2 story bricks can be used as a load bearing structure.
Standards for Bricks
Dimension Standard for Bricks
- Standard size of brick is 190x90x90 mm.
- Nominal size of bricks are 200x100x100 mm, which is included the 10mm of mortar all around.
- But in the practical life, most common size used at site in India is generally 9″x4.5″x3″ inches.
Technical Standard for Bricks
- The brick is generally categories into three types
- First class – superior quality having compressive value more than 100 N/mm2
- Second class – medium quality having compressive value more than 75 N/mm2
- Third class – Lower quality must have compressive value grater than 35 N/mm2
- A Brick should not absorb the 20% water in water absorption test conducted for 24 hours.
- A brick should not have any efflorescence effect.
- Irregular shape or Zhamma bricks are neglected.
Measurement of Bricks
Brickwork is measured in cubic metres or cubic feet.
The length, breadth and height is multiplied to calculate the total quantity used for any construction whether it is wall, pedestal or slab.
Note that: In government tenders the brickwork also measured in area, because it is assumed that the depth or width is fixed for any construction.
For Example look at a item specified in BSR
- Half brick masonry in foundation & plinth using bricks of designation 75 with nominal hoop rainforsed (2 Nos. 6mm MS bar) at every fourth course in for hoop rainforcement 1Sqm. 6mm MS bar 2x2x1.00 = 4.00 Cement mortar 1:6 (1Cement:6-coarse sand).Add extra over item No. 5.8 for half brick masonary in superstructure up to third story.
- The above item is measured in square metre and its price is 458.00 rupees per square metres.
Quantity of Brickwork:
As we measured the dimension of construction, the quantity is calculated as follows
- Lets
- Length = 3.05 metre or 10 feet
- Width = 0.23 metre or 9 inches
- Height = 3.05 metre or 10 feet
- Volume or Quantity = 3.05×0.23×3.05 = 2.14 m3 or cumec
Now we have our quantity of brickwork, so we can easily find out the actual bricks required for construction.
In this first we calculate the quantity required for standard size brickwork and after that same calculation for actual field size bricks.
Number of bricks and quantity of sand & cement is calculated in this step
TYPE 1: Standard Bricks CALCULATION
VOLUME = 2.14 m3
Standard Size of Brick = 190x90x90 =0.001539 m3
Nominal Size after mortar addition = 200x100x100 = 0.002 m3
Required Number of Bricks = 2.14/0.002 = 1070 Bricks
So Standard Number of Bricks for 1 Cubic metre = 1070/2.14 = 500 Bricks
Now Calculation of mortar ?
Mortar for 1 cubic metre = 500(200x100x100-190x90x90) = 0.2305 m3
Dry Mortar = 1.54×0.2305 = 0.35497 m3
Lets assume Mix ratio is 1:6 (1 cement and 6 sand)
- So required Cement = 1*0.35497/7 =0.05071 m3
- Cement in Kg = 0.05071×1440 = 73.02 Kg
- Required Sand = 6*0.35497/7 = 0.30426 m3
- Sand in Kg = 0.30426×1650 = 502.03 Kg
MATERIAL | QTY | UNITS |
Number of Bricks | 500 | Number |
Cement | 73 | Kg |
Sand | 502.03 | Kg |
Total Volume | 1 | M3 |
TYPE 2: Field Bricks CALCULATION
VOLUME = 2.14 m3
size of Brick used in field= 230x114x76 = 0.00199272 m3
Nominal Size after mortar addition = 230x124x86 = 0.00245 m3
Here we does not add mortar along length of brick because generally nowadays 9″ inches wall is considered and outer face is calculated as plaster area. You can add mortar if width of wall is more than 1 brick.
Required Number of Bricks = 2.14/0.00245 = 873 Bricks
So Actual Number of Bricks for 1 Cubic metre in field = 873/2.14 = 408 Bricks
Actual number varies from meson to meson because some one use less mortar and some one use more mortar. so it is mainly 390 to 430.
Generally local contractor consider 420 bricks in 1 cubic metre.
Now Calculation of mortar ?
Mortar for 1 cubic metre = 408(230x124x86-230x114x76) = 0.18768 m3
Dry Mortar = 1.54×0.18768 = 0.2890 m3
Lets assume Mix ratio is 1:6 (1 cement and 6 sand)
- So required Cement = 1*0.2890/7 =0.0412 m3
- Cement in Kg = 0.0412×1440 = 59.45 Kg
- Required Sand = 6*0.2890/7 = 0.2477 m3
- Sand in Kg = 0.2477×1650 = 408.70 Kg
MATERIAL | QTY | UNITS |
Number of Bricks | 408 | Number |
Cement | 59.45 | Kg |
Sand | 408.7 | Kg |
Tatal | 1 | M3 |
Hope this will help you, Thanks for reading. Enjoy
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