Chaining on Sloping Ground | Guide to Surveying and Levelling

Chaining on Sloping Ground | Surveying and Levelling

There are two methods for determining horizontal distance on sloping ground.

  1. Direct Method
  2. Indirect Method

Direct Method of Chain Surveying

This method is also known as “Stepping Method”.

The horizontal distances are directly measured by the process of stepping.

Procedure

A path of chain or tape is stretched out from ‘P’.

The path length of chain or tape depends on the steepness of the ground.

The follower holds the zero end of the chain at ‘P’ and directs the leader at P1 to be in the line of PQ and stretch the chain or tape above the ground in horizontal line.

Direct Method | Chain Surveying
Direct Method | Chain Surveying

The leader then transfers the point ‘P1’ to P2 on the ground by means of plumb bob or dropping a pebble or an arrow,

Now the followers take the new position ‘P2’ and directs the leader to move forward and stretch the tape or chain in a line of PQ.

Now the followers take the new position ‘P2’ and directs the leader to move forward and stretch the tape or chain in a line of PQ and the new position is P3.

Again the leader transfers the point P3 to P4 on the ground as done earlier.

This process is repeated till the point Q is reached.

Horizontal distance PQ = S1 + S2 + S3 + S4 + S5

Read moreChaining on Sloping Ground | Guide to Surveying and Levelling

Classification of surveys according to their Purpose | Civil Engineering

Classification of  Surveys according to their Purpose

In our previous article, we discussed division and classification of surveys based on various factors such as Purpose, instruments, field of work, method of work etc.

In this article, we will discuss different types of surveys carried out for various purposes in the field of Surveying

Mine Survey

Mine survey involves exploration of mineral wealth in the country. This would include minerals such as Gold, copper, coal, silver etc. between the earth’s crust.

Mine Survey
Mine Survey

Geological Survey

Geological Survey is carried out by geologists. It is usually for the purpose of the study of earth’s rock structure. It helps to determine different strata in the earth’s crust.

Archaeological Survey

As the name suggests, Archaeological Survey is carried out by the Archaeologists for the purpose of their study concerning the past. This survey helps to trace the relics of the past.

Read moreClassification of surveys according to their Purpose | Civil Engineering

Types of Scales in Engineering Surveying

Types of Scales | Engineering Surveying

In the previous article, we discussed briefly on the topic of “Scales in Surveying” where we came across an important term “Representative factor” which forms an important part in understanding the scales in Surveying.

In this article, we will discuss different types of scales used in Surveying…

The scales are classified into four categories:

  1. Plain Scale
  2. Diagonal Scale
  3. Vernier Scale
  4. Scale of chords

Lets go on with the discussion of types of scales briefly for our better understanding…

Plain Scale

Plain Scale is one on which it is possible to measure two dimensions only. For example, measurements such as units and lengths, metres and decimetres etc.

Plain Scale
Plain Scale

Six different plain scales in metric used by engineers, Architects and Surveyors.

Diagonal Scale

On diagonal scale, it is possible to measure three dimensions such as metres, decimetres and centimetres, units , tens and hundreds; yards, feet and inches etc.

A short length is divided into number of parts using the principle of similar triangle in which sides are proportional.

Read moreTypes of Scales in Engineering Surveying

Methods of Calculation of Areas in Surveying | Simpson’s Rule

Calculation of Areas in Surveying | Simpson’s Rule

In one of my previous articles, I discussed Midpoint Ordinate Rule and Average Ordinate Rule in detail with an example and listed out various important methods used for the calculation of areas in Surveying. In this article, we will deal with the next important method (rule) i.e. Simpson’s Rule along with a numerical example used for the calculation of areas in the field of Surveying.

Here are the five important rules (Methods) used for the calculation of areas in Surveying:

  1. Midpoint ordinate rule
  2. Average ordinate rule
  3. Simpson’s rule
  4. Trapezoidal rule
  5. Graphical rule

Simpson’s Rule

Statement

It states that, sum of first and last ordinates has to be done. Add twice the sum of remaining odd ordinates and four times the sum of remaining even ordinates. Multiply to this total sum by 1/3rd of the common distance between the ordinates which gives the required area.

Where O1, O2, O3, …. On are the lengths of the ordinates

d = common distance

n = number of divisions

Note:

This rule is applicable only if ordinates are odd, i.e. even number of divisions.

If the number of ordinates are even, the area of last division maybe calculated separated and added to the result obtained by applying Simpson’s rule to two remaining ordinates.

Read moreMethods of Calculation of Areas in Surveying | Simpson’s Rule