What do moisture-density relationships indicate in aggregate compaction?

Moisture-density relationships illustrate how the presence of moisture influences the maximum dry density of an aggregate material. This relationship is crucial for understanding how moisture affects compaction during construction projects. When moisture is added to aggregate materials, it can help lubricate particles, allowing them to rearrange and compact more effectively. The moisture-density curve typically shows that there is an optimal moisture content where the maximum dry density is achieved. At moisture levels below or above this optimum, the density will generally decrease, highlighting the significance of moisture content in achieving optimal compaction of aggregates. Understanding this relationship is essential for ensuring that aggregate bases meet required specifications and perform well under loads.