Various Types of Scales in Surveying
This construction article sheds light on various types of scales employed in Surveying
The scales are categorized as follows:
- Plain Scale
- Diagonal Scale
- Vernier Scale
- Scale of chords
Necessary data for RCC Rate Analysis:
- Computation of materials
- Bags of cement necessary
- Volume of Sand necessary
- Volume of Coarse Aggregate necessary
- Computation of Reinforced Steel
- Labour Requirement for 1m3 of RCC
- Equipments and sundries
- Contractor’s Profit
On Plain Scale, it is reasonable to calculate two dimensions only. As for instance, measurements like units and lengths, metres and decimetres etc.
The engineers, Architects and Surveyors generally employ six different plain scales in metric.
On diagonal scale, it is reasonable to calculate three dimensions like metres, decimetres and centimetres, units , tens and hundreds; yards, feet and inches etc.
A short length is seperated into number of parts by applying the principle of equivalent triangle in which sides are proportional.
- 1-1 represent 1/10 PQ
- 2-2 represent 2/10 PQ
- 9-9 represent 9/10 PQ
It is an effective tool for measuring the fractional part of one of the smallest divisions of a graduated scale.
It generally contains a small auxiliary scale that slides side by side of the main scale.
Least count of the vernier = the variation among smallest division on the main division and smallest division on the vernier scale
With scale of chords, it is possible to estimate an angle and is marked on either on rectangular protractor or an ordinary box wood scale.