Best Practices for Soil Compaction
Add stability and load-bearing capacity to soil with proper soil compaction. Follow these helpful tips to prevent soil settlement and water seepage to reduce unnecessary maintenance costs and prevent structural failures.
Utilize the proper equipment
Choose a machine that applies a vibratory force to the soil, such as vibratory or oscillating rollers, to achieve the best results. A rapid series of blows are applied to the surface of the soil, which impacts the deep layers below the surface, resulting in more consistent compaction.
When working with cohesive soil, a pad-foot roller should be used, while vibratory rollers are ideal for working with granular soils. When using non-vibratory rollers, the degree of compaction depends on the weight of the machine. The heavier the machine, the more effective the compaction.
Understand the soil
Before you begin compacting, you must identify the soil group you are working with. Different soil types have different maximum densities and optimum moisture levels that can impact results and consistency. The three basic soil groups are: cohesive, granular, and organic. Cohesive soils, such as clay, have particles that stick together. Granular soils, such as sand, have no clay content, and crumble easily. Organic soils are not suitable for compaction.
Establish the moisture level
It’s important to determine how wet or dry the soil is before you begin compacting. Soil that is too dry can result in inadequate compaction, while soil that is too wet can weaken stability. The easiest way to test the moisture content of soil is the “Hand Test.” Pick up a handful of soil, squeeze it, and then open your hand. You want the soil to be moldable and break into a few pieces when dropped. If the soil is powdery and shatters when dropped, it is too dry. If the soil leaves moisture in your hand and remains in one piece when dropped, it has too much moisture.
Always inspect the jobsite for dangerous inclines or declines. When operating rollers and compactors on uneven surfaces, the rollover hazard is increased significantly. Some machines are equipped with rollover protective structures (ROPS) to greatly reduce the risk of injury in the event of a rollover. However, the best protection from rollovers is to avoid them entirely.
Do not overcompact
If you make too many passes in one direction, you can overcompact the soil. Overcompaction reduces soil density, wastes time, and causes unnecessary wear on your machine. Train your operators to follow proper compaction methods, which will help prevent overcompaction.
Exercise caution during trench compaction
Before starting trench work, make sure that someone knowledgeable about OSHA requirements inspects the excavation site daily before each shift, and as needed throughout the shift. When possible, use remote control compaction equipment to protect your workers from cave-ins and falling objects.