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Soil stabilizers convert apparently less bearing ground into highly suitable one for starting construction work like pavements, road beds, basement of canals, water reservoir, etc. Soil stabilizationis the method of strengthening the ground through pulverization and moisture conditioning. This job is efficiently done with different forms of lime and then compaction and trimming as necessary. This process improves the basic characteristics of soil that makes it suitable for a construction project. Lime is used in different percentage depending on the soil condition to adjust the parameters like moisture, density, plasticity, permeability, strength, etc.

Benefits of soil stabilization

Soil stabilization with lime before starting any construction work has the following benefits:

• Apparently wet soil that is not suitable for construction work can be made suitable within one or two days.
• Treatment with lime ensures production of long-lasting stable jobs comparable with graded aggregates.
• The soil becomes hard wearing with greater toughness and strength that make it extremely suitable for a construction process.
• It enables recycling ofinsitu materials and existing soil that ultimately provides financial benefits to the contractor or owner of the land. It takes less time to prepare the soil as also saves expenses in labor, transportation, and import of aggregates.
• Soil stabilization with lime also reduces PI (Plasticity Index) of the existing soil significantly.
• The ground gains strength significantly that is found to be more than 15% as per CBR test.
• This process of soil stabilization is environmental-friendly too. The process requires very small quantities of other additives making less transportation of materials, less disturbance in busy areas, and lesser use of factory made binders.

Lime efficiently stabilizes weak soil

Use of lime as a stabilizer for road beds has been in practice over the century. Modern research works have proved behind doubt that lime can also be used for stabilizing the soil in the large construction sites. Lime is especially useful when expansive clay is present is a construction site. Expansive clays destabilize the base work and change the orientation of the concrete slabs with time. Whereas the soil treated with lime can solve the issue permanently. Lime actually performs a chemical stabilization process where the added lime compound reacts with the clay present in a ground in the following ways:

• When lime is mixed with the soil, the clay particles come together forming stiffer silt, and reducing plasticity of the soil.
• After the compaction job, life further reacts with the soil particles binding them firmly and increasing their strength.

Quicklime for soil stabilization in construction works

Many types of lime compounds are available, but quick lime or calcium oxide is mainly used for this work. Quicklime reacts with soil water forming calcium hydroxide which again reacts with some existing minerals like silica and alumina initiating an ionic exchange reaction forming a cement-like product naturally. In this reaction, called pozzolanic reaction, cannot retain water particles anymore and with the passage of time, it hardens like cement. Thus, quicklime provides the required stability to the soil.