What action should be taken if a soil compaction test fails due to low moisture content?

When a soil compaction test fails due to low moisture content, the appropriate action is to rip up the area, add water, and then recompacted. This approach addresses the root cause of the failure, which is insufficient moisture in the soil.

Moisture content plays a crucial role in the compaction process. When soil particles are too dry, they don't have the necessary lubrication to move closer together, which prevents achieving the optimal density and strength required for the specific application. By ripping up the soil, the operator increases the surface area exposed to moisture, allowing water to penetrate evenly throughout the soil. After adding the appropriate amount of water, recompacting ensures that the soil particles are properly oriented and densified, thus meeting the standards required for the project.

This method effectively transforms the soil's properties to achieve the desired compaction levels, supporting the structure or surface being constructed. Other actions, such as ignoring the test or simply adding more stone, do not address the underlying moisture deficiency and are unlikely to lead to an effective solution. Changing the compaction method may not solve the problem if the moisture content is the limiting factor, hence recompacting after proper moisture adjustment is the best course of action.