Weak soils lead to foundation settlement or hillside settlement which could mean disaster for your home.
Soil is a naturally-occurring mixture of mineral and organic ingredients with a definite form, structure, and composition. It’s composed primarily of minerals that are produced from parent material which is broken into small pieces by weathering. Larger pieces are stones, gravel, and other rock debris. Smaller particles are sand, silt, or clay. Since the original materials vary from place to place, the exact composition of soil varies according to location. A common example of soil composition by volume might be:
Notice that water is a key element in optimal soil make-up. Too much or too little water can cause settlement or movement in the soils supporting a foundation. Differential settlement occurs when the soil under one portion of a foundation settles at a rate greater than at other foundation locations. This can cause cracking, shifting of the supported building structural members, out of level floors, out of plumb walls, and sticking doors and windows.
Settlement occurs because all soils compress to some degree. Therefore, if a foundation is not on bedrock, it settles. It settles when there is a reduction in the voids in the soil supporting the foundation. Voids contain air and water, and void reduction is caused by the weight of the foundation and its supporting structure compressing the soil and reducing the void space. Compression varies according to the makeup of the soil.
The soil stabilization process is the alteration of soil to enhance its physical properties. Stabilization increases the strength of soil as well as control the shrink-swell properties of soil, improving the load-bearing capacity of sub-grade material to support concrete and structural foundations.
In other words, this process can assist in the prevention of settlement beneath slabs and foundations.