Atterberg limits

 Atterberg limits are a set of tests used to determine the properties of soil that are related to its ability to undergo deformation. These tests are named after their inventor, Albert Atterberg, a Swedish scientist.

There are three primary Atterberg limits tests that are commonly used:

1. Liquid Limit (LL): This test determines the water content at which a soil changes from a plastic state to a liquid state. It is determined by repeatedly dropping a standard device onto a soil sample until the soil starts to flow.

2. Plastic Limit (PL): This test determines the water content at which a soil changes from a plastic state to a semisolid state. It is determined by rolling a soil sample into a thread of a specific diameter.

3. Shrinkage Limit (SL): This test determines the water content at which a soil will no longer shrink when further dried. It is determined by drying a soil sample in an oven and measuring the change in volume.

These tests are used to classify soils based on their behavior under different moisture conditions. Soils with a high liquid limit tend to be more susceptible to deformation, whereas soils with a low plastic limit tend to be more resistant to deformation. The results of these tests can be used to predict the behavior of a soil under different conditions, which is important in many engineering and construction applications.