Sign Up

Sign Up to The Constructor to ask questions, answer questions, write articles, and connect with other people. VIP members get additional benefits.

Sign In

Login to The Constructor to ask questions, answer people’s questions, write articles & connect with other people. VIP members get additional benefits.

Free Signup or Login to continue Reading...

Forgot Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

Sorry, you do not have permission to ask a question, You must login to ask question. Become VIP Member

Free Signup or Login to continue Reading...

Get More Features, Sign Up Now. Become VIP Member

Print, PDF & Email

Soil stabilization with cement, bitumen, lime, chemical stabilization,geotextile, grouting etc. are discussed. It is a method of improving soil properties by blending and mixing other materials.

Soil Stabilization Methods with Different Materials

Following are the various soil stabilization methods and materials:

Soil Stabilization with Cement

The soil stabilized with cement is known as soil cement. The cementing action is believed to be the result of chemical reactions of cement with siliceous soil during hydration reaction. The important factors affecting the soil-cement are nature of soil content, conditions of mixing, compaction, curing and admixtures used.

The appropriate amounts of cement needed for different types of soils may be as follows:

  • Gravels – 5 to 10%
  • Sands – 7 to 12%
  • Silts – 12 to 15%, and
  • Clays – 12 – 20%

The quantity of cement for a compressive strength of 25 to 30 kg/cm2 should normally be sufficient for tropical climate for soil stabilization.

If the layer of soil having surface area of A (m2), thickness H (cm) and dry density rd (tonnes/m3), has to be stabilized with p percentage of cement by weight on the basis of dry soil, cement mixture will be


and, the amount of cement required for soil stabilization is given by

Amount of cement required, in tonnes = clip_image004

Lime, calcium chloride, sodium carbonate, sodium sulphate and fly ash are some of the additives commonly used with cement for cement stabilization of soil.

Soil Stabilization using Lime

Slaked lime is very effective in treating heavy plastic clayey soils. Lime may be used alone or in combination with cement, bitumen or fly ash. Sandy soils can also be stabilized with these combinations. Lime has been mainly used for stabilizing the road bases and the subgrade.

Lime changes the nature of the adsorbed layer and provides pozzolanic action. Plasticity index of highly plastic soils are reduced by the addition of lime with soil. There is an increase in the optimum water content and a decrease in the maximum compacted density and he strength and durability of soil increases.

Normally 2 to 8% of lime may be required for coarse grained soils and 5 to 8% of lime may be required for plastic soils. The amount of fly ash as admixture may vary from 8 to 20% of the weight of the soil.

Soil Stabilization with Bitumen

Asphalts and tars are bituminous materials which are used for stabilization of soil, generally for pavement construction. Bituminous materials when added to a soil, it imparts both cohesion and reduced water absorption. Depending upon the above actions and the nature of soils, bitumen stabilization is classified in following four types:

  • Sand bitumen stabilization
  • Soil Bitumen stabilization
  • Water proofed mechanical stabilization, and
  • Oiled earth.

Chemical Stabilization of Soil

Calcium chloride being hygroscopic and deliquescent is used as a water retentive additive in mechanically stabilized soil bases and surfacing. The vapor pressure gets lowered, surface tension increases and rate of evaporation decreases. The freezing point of pure water gets lowered and it results in prevention or reduction of frost heave.

The depressing the electric double layer, the salt reduces the water pick up and thus the loss of strength of fine grained soils. Calcium chloride acts as a soil flocculent and facilitates compaction.

Frequent application of calcium chloride may be necessary to make up for the loss of chemical by leaching action. For the salt to be effective, the relative humidity of the atmosphere should be above 30%.

Sodium chloride is the other chemical that can be used for this purpose with a stabilizing action similar to that of calcium chloride.

Sodium silicate is yet another chemical used for this purpose in combination with other chemicals such as calcium chloride, polymers, chrome lignin, alkyl chlorosilanes, siliconites, amines and quarternary ammonium salts, sodium hexametaphosphate, phosphoric acid combined with a wetting agent.

Soil Stabilization Methods and Materials

Electrical Stabilization of Clayey Soils

Electrical stabilization of clayey soils is done by method known as electro-osmosis. This is an expensive method of soil stabilization and is mainly used for drainage of cohesive soils.

Soil Stabilization by Grouting

In this method, stabilizers are introduced by injection into the soil. This method is not useful for clayey soils because of their low permeability. This is a costly method for soil stabilization.

This method is suitable for stabilizing buried zones of relatively limited extent. The grouting techniques can be classified as following:

  • Clay grouting
  • Chemical grouting
  • Chrome lignin grouting
  • Polymer grouting, and
  • Bituminous grouting

Soil Stabilization by Geotextiles and Fabrics

Geotextiles are porous fabrics made of synthetic materials such as polyethylene, polyester, nylons and polyvinyl chloride. Woven, non-woven and grid form varieties of geotextiles are available. Geotextiles have a high strength.

When properly embedded in soil, it contributes to its stability. It is used in the construction of unpaved roads over soft soils.

Reinforcing the soil for stabilization by metallic strips into it and providing an anchor or tie back to restrain a facing skin element.

More on Soil Stabilization

Gopal Mishra

Related Articles


  1. Another method of stabilizing/strengthening clay soils is an ion exchange process using sulphonated petroleum based solutions that can be either injected directly into the soil for building construction or applied topically after scarification when used for road construction. The solution is environmentally safe, easy to apply, permanent and costs 30 to 50% less than more traditional methods like cement or lime. Benefits of dewatering are also present when using ion exchangers. Much success has been achieved in it's use in Korea, China, Australia and the US.

  2. Soil stabilization plays a vital role especially in roads and bridges construction, in planning huge townships and layouts too we require soil stabilization. As described above various soils require different types of stabilization processes, but generally a single process is followed through out the road length, which is not correct. This we observe when we drive cross country, in some pockets we can see formation of humps because of soil settlement and wear and tear of road more in some areas. As the sub soil strata changes we too have to change the method of soil stabilization process, other wise the maintenance cost will be high.

    Also from the past experience we can decide upon the methods of soil stabilization.

Leave a comment

You must login to add a new comment.

Free Signup or Login to continue Reading...