Chain survey is a traditional land surveying method that involves measuring distances and angles on the ground using a chain or tape and a theodolite or compass. It is a simple and reliable method that has been used for centuries to survey land, determine boundaries, and create maps.
In a chain survey, a series of interconnected triangles are formed to determine the positions of the survey points. The length of the chain used in the survey is known as a chain line, and the points where the chain changes direction are known as chainage points.
The chainage points are marked on the ground using pegs or stakes, and the distances and angles between the points are measured using a chain and a theodolite or compass. The angles are measured using the theodolite or compass, while the distances are measured using the chain or tape.
Once the measurements have been taken, the surveyor can then use trigonometry to calculate the coordinates of the survey points and draw a map of the surveyed area. The accuracy of the survey depends on the skill of the surveyor, the precision of the equipment used, and the complexity of the terrain.
Chain surveys are still used today in some parts of the world, particularly in rural areas where access to modern surveying equipment is limited. However, modern surveying techniques such as GPS and total stations are increasingly being used in land surveying due to their higher accuracy and efficiency.
