To determine the tensile strength of rocks in UTM machine.

To determine the tensile strength of rocks in UTM machine.

EQUIPMENTS: UTM according to specifications listed in the ASTM code C-170, cleaning cloth, Vernier caliper with the accuracy of 0.1mm to measure the length and dia of core samples or scale.

SPECIMEN:Locally available rock cores free from discontinuities, cracks, fractures should be of regular sizes.

THEORY

Tensile Strength: Tensile strength is the maximumstressthat a material can withstand while being stretched or pulled before breaking. When loads are applied on the body which tends to stretch the body externally and the stress will produce internally which will resist it. Tensile strength is also measured in UTM, which is showed in figure

PROCEDURE

1. Choose the sample and standardize it.
2. To find out the dimension (length, dia, height) by Vernier caliper.
3. To clean the surface.
4. Calculate the cross section area of core by formula ² .where r = .
5. Place the sample horizontally in the UTM.
6. Note the initial load.
7. Also, note the final load where the sample breaks.

SAMPLES:

OBSERVATIONS

Rock Name:__________________________

Now the load can be calculated as load = P= final load – initial load

Formula for tensile strength= , Where P is load, L is length, and D is dia.

Generally, tensile strength is 10% of compressive strength.

Results:

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