Soil stabilizers assist in strengthening soil and increasing its water resistance. This allows the soil to be used later as a durable building material. Their use is quite beneficial, because it reduces movement, thereby eliminating or reducing the need for additional support for slabs or fill materials when building. The Ancient Romans were the first to experiment with mixing lime with sub-grade foundation soil to stabilize it. These Ancient Roman stabilizers failed, however, because the lime only improved the surface.
Today’s soil stabilizers work quickly and are inexpensive. There are three primary ways to use them to improve soil. One of these methods is to strengthen the existing soil, which enhances its load-bearing capacity. Others are used to control dust by preventing it or eliminating it altogether. Finally, waterproofing stabilizers assist in preserving the natural or constructed strength of the soil by protecting the surface from water.
Additives such as cement, lime, and calcium chloride are often found in soil stabilizers. Some also have a cement-treated base, which further helps to improve the soil’s quality. These soil-cement stabilizers are made of pulverized soil, cement, and water. The ingredients are compacted to a high-density.
Soil stabilizers are usually injected into the soil through a regulated pump at a pressure of 50 to 200 pounds per square inch (psi), or 345 to 1,379 kilopascals. High-pressure mud pumps are also sometimes used to inject stabilizers into the soil. The depth of these injections is often 3 to 10 feet (0.91 to 3.1 meters), though they can be as much as 40 feet (12.2 meters) deep. If the soil is stiff, holes are pre-drilled and the stabilizers are inserted within the soil.
This process of injecting them into the ground is completed with inflatable packers that plug the holes burrowed into the ground. The pressure created by the pump allows a greater flow of the soil stabilizers to penetrate the ground. When the process is complete, a network of horizontal seams and vertical or angular veins appears in the ground.