Why is it necessary to perform a soil compaction test?

Performing a soil compaction test is essential primarily to ensure that the soil meets project specifications for load-bearing capacity. This test measures the density of the soil after it has been compacted, which is directly related to its ability to support loads without excessive settlement or failure. A well-compacted soil structure contributes to the strength and stability of the foundation, pavement, or any structure being built above it. Meeting these specifications is critical for safety and longevity in construction, as inadequate compaction can lead to structural issues over time.

The other options, while related to aspects of soil testing, are not the primary reasons for conducting a compaction test. Assessing soil color, determining water content, and evaluating soil pH provide valuable information about the soil's physical and chemical properties, but they do not directly relate to the load-bearing capacity or the structural integrity needed in construction projects.