Why should we test CBR ?

 CBR - California Bearing Ratio

The CBR test is conducted to get CBR value for soil on which road have to be constructed.

CBR value is a measure of resistance of any material to penetration of standard plunger under contro0lle density and moisture content.

The CBR test gives CBR value for a given soil sample that tells about its resistance against penetration. After getting CBR value, we determine thickness of pavement and its constituent layers as per IS specifications.

In simple word, it gives bearing capacity of soil to resist vehicle loads and according to this value we calculate thickness of pavement for safe driving.

If CBR test doesn't conduct and sufficient thickness is not provided then defects like waves, corrugation, rutting in black top pavement and cracking in cement concrete pavement may takes place.

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