Degree of saturation is the percentage of saturated samples obtained from the field.
Active earth pressure occurs in active soils and passive earth pressure occurs in passive soils. The unconsolidated type triaxial tests, also known as the UU type, are performed on samples that are not preconsolidated in the field. Examples of active soils are San Fransisco Bay Mud and Boston Blue Clay, especially when active ingredients, such as sands and gravels, are added. A factor of safety on shear strength should be applied in any situation when there is reasonable doubt that they don't know how to measure the shear strength in the lab. Consolidated type triaxial tests, like CU and CD, are done on samples that are not preconsolidated already.