Sensitivity of Soil | Sensitivity Of Clay | Classification Of Soil Based On Sensitivity

The sensitivity of soil or sensitivity of clay can be defined as the ratio of the unconfined compression strength of soil or clay in the undisturbed state to the unconfined compressive strength of the same clay in the remoulded state, without any change in the content of water.

Sensitivity Of Clay Formula

The sensitivity of the clay formula is S_t= S_u(undisturbed) / S_u(Remoulded). Here S_t is the sensitivity of clay, and S_u is the unconfined compressive strength of the clay.

More Read- Thixotropy Of Clay

When the cohesive soil (soil with high clay content) is remoulded, it loses a part of its shear strength and the loss of shear strength of clay after remoulding is basically due to the change in the structure of clay particles.

Here we can also define the sensitivity of Soil as a measurement tool to measure the loss of the strength of clay or soil after remoulding it.

The clay is classified by its sensitivity value which is shown in the below table.

Sensitivity Of Soil Table | Clay Sensitivity Classification

Classification	Sensitivity
Insensitive	<1
Slightly Sensitive	1-2
Medium Sensitive	2-4
Very Sensitive	4-8
Slightly Quick	8-16
Medium Quick	16-32
Very Quick	32-64
Extra Quick	>64

More Read- Plasticity Of Soil | Why is Plasticity Of Soil Important?

Classification Of Soil Based On Sensitivity

Based on the sensitivity the soil or clay is divided into 8 parts which are given below.

1-Insensitive soil or clay having sensitivity less than 1.

2-Slightly Sensitive soil or clay having sensitivity between 1 to 2.

3-Medium Sensitive soil or clay having sensitivity values ranging from 2 to 4.

4-Very Sensitive soil or clay having sensitivity values ranging from 4 to 8.

5-Slightly Quick soil or clay having sensitivity values ranging from 8 to 16.

6- Medium Quick soil or clay having sensitivity values ranging from 16 to 32.

7-Very Quick soil or clay having sensitivity values ranging from 32 to 64.

8-Extra Quick soil or clay having sensitivity values greater than 64.

What are the properties of clay sensitivity?

Here are the following properties of clay sensitivity.

1- The sensitive soil has a higher moisture content, low dry bulk quantity, and possesses high porosity.

2- The liquidity index ranged between .27 to 2.41 and the plasticity index values range from 13.2% to 42.7%.

3- The sensitivity and remoulding strength is majorly controlled by the liquidity index.

4- Sensitivity is a measuring tool which measures the loss of strength of clay after remoulding.

Frequently Asked Questions (FAQ)