Estimating Practice Exam

The compaction factor refers to what in excavation practices?

1. The increase of soil volume

2. The efficiency of fill material usage

3. The decrease in volume after compaction

4. The overall density comparison

The correct answer is: The decrease in volume after compaction

The compaction factor in excavation practices is an important concept that quantifies the change in volume of soil or fill material when it undergoes compaction. Specifically, it refers to the decrease in volume after compaction occurs. When soil is compacted, air pockets are removed and particles are rearranged to occupy a smaller volume, which results in a more dense material. This decrease in volume is critical for achieving desired soil strength and stability in construction projects, as properly compacted soil ensures that the structure built upon it has a solid foundation. In contrast, other concepts like the increase of soil volume relate to swelling and changes in moisture content rather than compaction. The efficiency of fill material usage pertains to how effectively materials are used in a project but does not specifically address volume changes. Lastly, while overall density comparison can be relevant, it is a broader concept that does not specifically define what the compaction factor directly assesses. Thus, the correct understanding of the compaction factor is its direct relationship to the decrease in volume resulting from the compaction process.