Which test is typically not performed in the laboratory for soil analysis?

The field density test is generally performed in situ rather than in a laboratory setting. This test is essential for assessing the compactness of soil in its natural state, typically conducted by methods such as the sand cone method or nuclear density gauges. These techniques allow engineers to obtain density measurements directly from the ground where the soil will be subjected to load.

In contrast, the other tests mentioned, like the Atterberg limits test, standard proctor test, and unconfined compressive strength test, are all laboratory analyses. The Atterberg limits test evaluates the plasticity characteristics of fine-grained soils, the standard proctor test determines the optimal moisture content and maximum dry density of soil, and the unconfined compressive strength test assesses the strength of soil samples under unconfined conditions. Each of these tests requires preparing soil samples in a controlled laboratory environment to ensure accurate and consistent results.