Cement-Treated Base (“CTB”) is a strong base for both rigid or flexible pavements. CTB is made up of insitu soils and aggregates mixed with specific quantities of cement dust. Pavements now constructed in India with CTB are stronger than older granular base roads that have not been properly stabilized. When constructing with CTB, GRT has been able to reduce the thickness of the base for the same weight and traffic volumes and still meet all IRC codes. Properly engineered CTB pavements can distribute loads over wider surface areas significantly reducing stress on sub-grade and increases the load-carrying specification of flexible pavements. CTB can also be used as a sub base for concrete pavements. The rigid qualities of CTB reduce deflection and rutting in base layers and wear courses. The versatility of cement is key in this solution because site conditions and soil types, from Black Cotton to Murrum, can easily change across the diverse landscape of India.
CTB is widely used as a pavement base for highways, expressways, district roads, PMGSY, parking & hardstand areas, airports etc.
IN EXCESS OF 5 MILLION SQUARE METRES OF BASE LAYERS HAVE BEEN TREATED WITH CEMENT BY GRT
- Green field projects;
- Road widening;
- Black cotton soil areas;
- Volatile soil
- Low overall cost
The key to strength development in CTB base or subbase mixtures is in the matrix that binds the aggregate particles together. The strength of the matrix is affected by the cementitious material used in the mixture. The amount of cementitious material in a stabilized base or subbase mix usually ranges from 5 to 10 percent by weight of the mix.
In the field
The purpose of a stabilized base or subbase layer is to provide a transitional load-bearing strata between the pavement layer, which directly receives the wheel loadings of vehicular traffic, and the underlying subgrade soil. GRT uses state-of-the-art road recyclers to combine the cement. The cement material is spread evenly in loose layers on a prepared subgrade or subbase using automated spreader machines. Once the material has been spread and combined it is then densified by means of conventional rollers of compaction equipment.
GRT stabilised marginal soil usually not considered suitable for road construction, providing extraordinary results.