There are several steps in the estimation of the different types of structures like buildings, culverts, bridges, and roads. To measure different activities like excavation, plastering, brickwork, etc, we need units of measurement.
Estimation is possible only when we have unit rates and units of quantity. At the end of the article, I have embedded pdf. and a Video that will be helpful for you.
a. Earthwork can be done in cutting and filling.
b. Measurement unit:- Per 100 m3 or per cum.
c. The payment includes up to 50 m lead and 1.5 m lift.
d. Lead represents the horizontal moment of soil and lift represents the vertical movement of soil.
2) Surface excavation
When the planned area of the earthwork is more than 10m2 and the width of the earthwork is more than 1.5m but the thickness of the earthwork is less than 50cm, the earthwork is known as surface earthwork.
a. Unit of measurement:- per m2
b. Mode of payment:- Per 100 m2 or per % m2
1. When the soil is soft, one layer of rigid material is applied over the soil, which is known as soling.
2. Unit of measurement:- per m2
3. Mode of payment:- per m2
4. Rigid material layer can be of dry bricks and stones.
4) Bricks work/masonry work
a. Unit of measurement = m3
b. For Partition wall or 4” wall or half brick thickness wall, measurement unit = m2
c. For the honeycomb wall, Measurement unit = m2
d. For the opening area in walls up to 1000 cm2 no deductions are applied.
e. For opening areas more than, 1000 cm2 deductions are applied.
f. For end c/s of the beam up to 500cm2 area, no deductions are applied.
g. For areas above 500cm2, deductions all are applied.
5) RCC and R.B work
a. Cement concrete and brickwork = m3
b. R/F measurement unit = kg
c. Density of mild steel = 7850 kg/m3
M=E x v
Q) calculate the quantity of steel bars used in reinforcement having dia in 25 mm oval 10 m length.
M= 38.58 kg
Q) A beam contains 4 bars of 20m dia. Calculate the quantity of steel per unit length.
a. For calculation RCC work.
b. In the case of steel roof truss, 5% quantity of steel is provided for riveted and bolted connections.
c. For one door, six(6) hold fast are provided. For windows, 4 hold-fast arrangements are provided.
d. The maximum weight of each hold-fast arrangement is 1-1.5kg
e. If detailed measurements is not given,
f) for columns, 1 % to 5% by volume.
g) For beams, 1% to 2% by volume.
c) For slab, 0.5% to 1% by volume.
Note:- Threading of steel is done in terms of running length (cm)
7) Damp-proof course
a. DPC consists of a standard water-proofing arrangement provided with cement concrete.
b. Thickness of DPC 2cm to 4cm (Avg-2.5cm)
c. DPC is provided on the plinth level.
d. DPC is not provided at door openings.
e. Measurement unit – m2
f. DPC basically consists of standard cement concrete (m20) or (m15) mixed with waterproofing material.
a. The thickness of plaster is 12mm, 15mm, or 20mm.
b. Measurement unit:- m2 with specified thickness of plaster.
c. No deductions are applied for the end of the beam.
|Double-sided deductions||Double-sided deductions|
|(a) Upto 0.5m2||No deductions|
|(b) 0.5 to 3m2||Single sided deductions|
|(c) > 3m2||Double sided deductions|
5. Plaster work is always provided on both sides of the wall.
a. Plaster represents a water seal which is provided in the form of cement mortar b/w brickwork.
b. Pointing is generally provided for the members which are exposed to the atmosphere or at the outside of the structure where is not done.
c. Measurement unit –m2
a. It represents a corner design that is provided for decorative purposes.
b. Measurement unit – running length or m.
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