Study Guide For Basic Paver Installation (Section 1 of 5, Soil Identification & Sub-Grade Prep)

In almost all brick paving installations there will be a fair amount of excavation involved to accommodate for the proper base that is required on a successful brick paving project. It is important that you have a basic understanding of the different types of soil you may encounter, as they can have an overall impact on your project. Different soils respond differently to the various elements at hand, such as ( water, frost and traffic loads ). So in this section we will take a look at the different soils that exist as well as proper sub-grade preparation writing essay service


In general there are five basic soil groups: gravel, sand, silt, clay and organic soils. The first one is gravel. Gravel contains individual grains ranging in sizes from.08 up to 3 inches in diameter. The second soil type is sand. Sand is mostly comprised of mineral fragments smaller than.08 in diameter with a semi-sharp appearance. The third soil type is silt. Silt has extremely fine grains which gives silt a very soft appearance when dry. The fourth soil type is clay. Clay is a very fine texture soil which becomes very sticky when wet and forms very hard lumps when dry. The fifth soil type is organic matter. Organic matter consists of decomposed plant material along with organic peat, organic clays and silts.

Now that we know what the five basic soil groups, lets take a look at how to identify the various soils at hand. The best way to identify soils on your project is to do a visual soil inspection. Here is what to look for in the various soils.

Sand = sand is very free flowing when in its dry form. It will form a cast when it has moisture available, but it will fall apart when handled. It is also granular in appearance.

Sandy loam = sandy loam is granular in appearance with the predominate characteristics of sand. It also contains silt and clay which allows it to form a cast when moisture is present. The cast itself will fall apart when handled. Sandy loams are generally free flowing when dry.

Loam = loam is generally a uniform mixture of sand, silt and clay. It has a grainy feel, but it is generally smooth in appearance. Loam will form a cast with moisture and can be handled freely without breaking. Loam in its dry form will hold a cast that can be handled with care.

Silt loam = silt loam contains a more consistent amount of finer grades of sand and over 50% silt with a small amount of clay in the mixture. When silt loam is in its dry form it can appear to be rather solid but can be pulverized into a powder. Silt loam will form a cast when wet and it can be handled freely.

Silt = silt mostly contains silt particles with fine sand and clay. Silt, much like silt loam in its dry form, will give the appearance of a solid mass, but it can be easily pulverized. Silt with moisture present will form a cast that can be handled. It will also easily puddle.

Clay loam = clay loam is a fine texture soil which contains more clay than silt loam. It can break into clumps in its dry form which sometimes resembles clay. Clay loam, in its wet form, forms a cast that can be handled without breaking.

Clay = clay is also a fine texture soil and breaks into hard clumps that are difficult to pulverize. When moisture is added to clay it very easily forms a cast that can be handled freely.

Organic soils = organic soils consist mostly of decomposed organic material, a considerable amount of mineral content and a little fibrous material. Fibrous organic soil would be classified as organic peat, which contains mostly fibrous plant remains. The soil colors of organic soils and fibrous organic soils can range from a rich brown to a dark black. Organic soils have considerable shrinkage in size upon drying.