Answer:

Introduction:
The sensitivity of clay is a measure of the changes in its strength properties between its natural and remoulded states. It is an important property in geotechnical engineering as it affects the stability of slopes, foundations, and embankments. This question asks us to determine the sensitivity of a clay sample based on its unconfined compressive strength.

Calculation:
The sensitivity of clay is defined as the ratio of its unconfined compressive strength in the natural state to its unconfined compressive strength in the remoulded state. We are given that the unconfined compressive strength of the clay sample is 4 kg/cm2 in its natural state and reduces by four times in the remoulded state. Therefore, the unconfined compressive strength of the clay sample in its remoulded state is 1 kg/cm2.

The sensitivity of the clay sample is calculated as follows:

Sensitivity = (Unconfined compressive strength in natural state) / (Unconfined compressive strength in remoulded state)
Sensitivity = 4 / 1
Sensitivity = 4

Therefore, the sensitivity of the clay sample is 4.

Explanation:
The sensitivity of clay is an important property in geotechnical engineering because it affects the stability of slopes, foundations, and embankments. Clay samples with high sensitivity are more prone to shear failure and liquefaction than those with low sensitivity. The sensitivity of clay is affected by various factors such as its mineralogy, structure, and moisture content.

In this question, we are given that the unconfined compressive strength of the clay sample reduces by four times in the remoulded state. This indicates that the clay sample is highly sensitive as its strength properties change significantly when it is disturbed. The sensitivity of the clay sample is calculated as 4, which is a relatively high value and indicates that the sample is highly sensitive.

In summary, the sensitivity of clay is a measure of the changes in its strength properties between its natural and remoulded states. The sensitivity of a clay sample is affected by various factors and is an important property in geotechnical engineering. The sensitivity of the clay sample in this question is calculated as 4, indicating that the sample is highly sensitive.

4