Getting the job done right the first time is paramount, and it all starts with one of the most critical processes—compaction.
Demolition of in-ground swimming pools involve backfilling the cavity with clean fill material, which is typically soil. When soil is broken free from the ground, air molecules enter the soil and cause the soil to fluff (expand) by as much as 30%.
The key to a successful backfill of a swimming pool cavity is to achieve proper compaction by using proper equipment and compaction methods. Poor compaction can result in settlement of the soil. This creates future maintenance issues.
The soil placed in the swimming pool cavity is full of air molecules. Air molecules will eventually go away on over time, the soil will self-compress, also known as settlement. The objective is to take steps to aid in preventing settlement.
Many contractors will tell you they are going to “compact” the fill material, but with what? Many contractors believe that simply driving their skid steer loader (Bobcat) over the loose fill material is a sufficient compaction method. This is not true, driving a skid steer loader is not the correct way to achieve adequate compaction. A skid steer loader does not create centrifugal force, which is necessary to push the air molecules out of the soil. Merriam-Webster Dictionary defines centrifugal force as – the apparent force that is felt by an object moving in a curved path that acts outwardly away from the center of rotation.
The most effective way to achieve maximum density compaction of fill material is by using a vibratory soil compactor, such as a trench roller. The vibratory drums hit the ground with much greater force than their static weight.