Specifically, the plasticity index refers to that the soil gradually becomes soft and plastic from the driest state after proper water addition, until it can just be shaped into a certain shape (commonly used shapes are? 3mm, the length is 10mm? Soil quality), the ratio of water to soil dry weight. The greater the ratio, the better the plasticity of soil, on the contrary, the worse the plasticity of soil.
Plasticity index is a commonly used parameter in soil engineering, which plays an important role in soil classification, soil engineering design and foundation treatment. Usually, the greater the plasticity index, the higher the viscosity and plasticity of soil, but too high plasticity index will also lead to poor fluidity of soil, which will have an adverse impact on engineering construction. Therefore, it is very important to evaluate the plasticity index of soil correctly.