The Unified Soil Classification System (USCS) is widely used in the United States for classifying soils based on their grain size distribution, plasticity, and other properties.

Shear strength is the ability of a soil to resist deformation under shear stress, which is the stress that causes one part of a soil mass to slide past another.

Permeability is the ability of a soil to allow water to flow through it. It depends on the size and interconnectedness of the soil pores.

Lateral earth pressure is the pressure exerted by soil on a structure that is in contact with it, such as a retaining wall or a foundation.

Pile foundations are deep foundations that transfer the load of a structure to a deeper, more stable soil layer. They are often used for structures that require high bearing capacity and resistance to settlement.

Geotextiles are often used in foundation engineering to improve the drainage of the soil, which can help to reduce the risk of settlement and other problems.

Cohesion is the ability of a soil to resist deformation under shear stress due to the attraction between soil particles.

Soil testing is the process of determining the properties of a soil, such as its grain size distribution, plasticity, and shear strength.

Spread footings are shallow foundations that distribute the load of a structure over a large area. They are often used for structures that require a large bearing area and are subjected to moderate loads.

Compaction is the process of compacting soil to increase its density and strength. It is often done using heavy machinery.

Compressibility is the ability of a soil to deform under load without rupturing. It is the opposite of stiffness.

Bearing capacity analysis is the process of determining the bearing capacity of a soil, which is the maximum load that the soil can support without failing.

Pile foundations are deep foundations that transfer the load of a structure to a deeper, more stable soil layer. They are often used for structures that require a high degree of resistance to lateral forces, such as wind or seismic loads.

Settlement analysis is the process of determining the settlement of a structure, which is the downward movement of the structure due to the compression of the soil beneath it.

Cohesion is the ability of a soil to resist erosion due to the attraction between soil particles.