What is one potential effect of compaction on aggregates in freezing conditions?

In freezing conditions, compaction of aggregates can lead to the potential effect of decreased load-bearing capacity. This occurs because when moisture is present in the aggregates, compaction can trap water within the material. As temperatures drop and the water freezes, it expands, leading to internal stresses that can damage the structure of the aggregate. This damage can reduce the overall strength and load-bearing capacity of the compacted material, making it less able to support loads effectively.

Compaction is generally intended to enhance the density and interlock of aggregate particles, but in cold weather, the effects of freezing can counteract these benefits by introducing vulnerabilities. The presence of ice within the structure can create voids and reduce the effective contact between particles, contributing to a decline in the load-bearing capacity of the base layer.

Understanding this phenomenon is crucial for engineers and technicians, especially in areas prone to freezing, as it emphasizes the importance of managing moisture content during the compaction process. This consideration is vital in ensuring the long-term performance and stability of aggregate bases in cold climates.