METHOD OF CHAINING ON METHOD OF CHAINING ON SLOPING GROUNDSSLOPING GROUNDS

There are two methods of chaining on There are two methods of chaining on

sloping groundssloping grounds

Direct method Direct method

Indirect methodIndirect method

Direct methodDirect method

In this method the sloping ground is divided into a number of horizontal and vertical strips

The lengths of horizontal portions are measured and added to get the total horizontal distance

Indirect method

There are further three types of indirect method By using clinometerBy applying hypotenusal allowanceBy knowing the difference of level between the points

By using clinometerA clinometer is a graduated semicircular protractorWe measure the slope of the ground by using clinometerWe resolve the sloping distance into its horizontal component by using the formula

Horizontal component =(magnitude of sloping distance )(cosα)

Horizontal component is the required distance

By applying hypotenusal allowance

In this method the slope of the ground is found by clinometer Hypotenusal allowance is made for each stepThen hypotenusal allowance is applied on each step until the end of line is reached

A

C

Knowing the difference of level In this method the difference of level of

two points on the slope is measured by a levelling instrument

Then the sloping distances are measured

A triangle will form then by applying pathagorous theorem the horizontal distance is measured