Construction Cost Estimating


Some vital tips to measure the load on the concrete columns

The load operating on the concrete column can be easily calculated manually.

Types of loads on the column

1. Self weight of the column x Number of floors
2. Self weight of beams per running meter
3. Load of walls per running meter
4. Complete load of slab (Dead load + Live load + Self weight)

The columns are exposed to bending moments which should be included in the final design.

In professional system, some basic assumptions are considered while making estimations for structural loading.

For Columns: Self weight of Concrete remains 2400 kg per cubic meter approximately, that is identical to 240 kN. Self weight of Steel remains 8000 kg per cubic meter approximately. Consider a large column size of 230 mm x 600 mm with 1% steel and 3 meters standard height, the self weight of column is approximately 1000 kg per floor, that is identical to 10 kN. The self weight of column should remain among 10 to 15 kN per floor.

For Beams: The calculation is same as above. Suppose, each meter of beam contains dimensions of 230 mm x 450 mm exclusive of slab thickness. Therefore, the self weight is approximately 2.5 kN per running meter.

For Walls: Density of bricks fluctuates among 1500 to 2000 kg per cubic meter. For a 6″ thick wall with 3 meter height and 1 meter length, the load can be measured per running meter to be equivalent to 0.150 x 1 x 3 x 2000 = 900 kg that is identical to 9 kN/meter. It is possible to work out the load per running meter for any brick type with this method.

For autoclaved, aerated concrete blocks similar to Aerocon or Siporex, the weight per cubic meter remains among 550 to 700 kg per cubic meter. When these blocks are used in construction, the wall loads per running meter remains as low as 4 kN/meter, that leads to significant curtailment of construction cost.

For Slab: Suppose, the slab contains a thickness of 125 mm, now the self weight of each square meter of slab will be 0.125 x 1 x 2400 = 300 kg that is identical to 3 kN.

Now, takes finishing load as 1 kN per meter and superimposed live load as 2 kN per meter. Therefore, the slab load is measured as approximately 6 to 7 kN per square meter.

Factor of Safety: In the end, after measuring the entire load on a column, it is also necessary to add in the factor of safety. For IS 456:2000, the factor of safety is 1.5.

Some vital tips to measure the load on the concrete columns