Driveway Soil Types: The Key For A Stable Driveway Base

The condition of the base soil is a major consideration in laying out a driveway. This is one of the first things that contractors put in mind in concrete driveway installation. This is due to the fact that not all areas in United States or anywhere else have the same type of soil. For example, the type of soil you can find in the valleys of Colorado and coastal plains of Los Angeles is different from the type of soil in the hills of the Southern areas. The latter have subsurface soil layers that restrict water flow and root penetration while the former have expansive soils that crack when they dry. Knowing the condition of soil would determine how your driveways should be constructed.

          The condition of soil underneath a driveway would surely affect the quality and performance of your concrete driveway. If soil condition is not properly addressed or considered during driveway planning and design, issues related to leveling, cracking and structural damages may occur. The capacity of a driveway to support traffic is heavily dependent to the condition of soil.

          Generally, the type of soil used for driveways is classified into three: on-site, caliche and aggregate. On-site soil is the soil that is found just right there lying on the path where you will install your concrete driveway. Clay and loam are examples of an on-site soil. Sand, gravel and nitrate particles belong to the second type of driveway soil which is caliche soil. Nitrate particles are made of lime or calcium carbonate. Caliche soils are clumps or layers of cream to white colored soils and they become dusty. Aggregates, the third type, are made up loose aggregation of minerals, gravel and crushed rocks. 

          Now, let us describe the characteristics of each soil types, there influence to the performance and quality of a driveway and some remedies that can be done to cope with characteristics. Clay and loamy soils retain water since they are soft. As an effect, they can move under concrete driveway, leading to cracking. Some homeowners see excavation as the only solution here and replace the soil with crushed rocks, but this is not always the last resort. A Geotechnical fabric can be placed between on-site soils and crushed rocks to have a firmer driveway base. 

   

          Sand and gravel are considered the ideal soils for concrete driveway because they can be compacted easily, drain water quickly and prepared easily. They don't also allow root penetration or plant growth, things that can settle the base and damage the driveway. Although caliche soils are dusty, this can be remedied by spraying them with emulsions.  Aggregates like crushed rocks are usually placed as toppings to the sub base soil. They are applied in two inches thick atop a native soil.

          The key to a driveway with good performance and easy to maintain is the condition of the soil being used as its base. Making amendments to soil or even just by being aware about what type of soil it is would give you a driveway with a strong, solid and stable base.