What is the primary purpose of conducting a 'field density test'?

The primary purpose of conducting a field density test is to determine the in-place density of compacted soil or asphalt layers. This test is crucial for assessing whether the materials used in construction have achieved the required density for structural integrity and performance. Achieving the proper density ensures that there is sufficient compaction to provide stability and prevent issues such as settlement or failure under traffic loads.

Field density tests help in verifying that the construction methods employed are effective and meet the specifications outlined in project plans. By knowing the in-place density, inspectors can infer the level of compaction and adjust processes as needed to meet design specifications.

While assessing the air void content of asphalt, evaluating moisture content, or measuring temperature might provide relevant information during construction, these tests do not directly measure the compacted state of the material itself in terms of density. Their focuses are different; hence they do not fulfill the primary role that field density tests do.