Trinidad Cement Limited (TCL) has been an advocator of green and sustainable engineering in the campaign of reducing its carbon footprint. Therefore, significant research and development into greener cements and alternative uses of cement are ongoing for continuous improvement in the manufacturing and construction sector.
TCL has thus far launched a “blended pozzolanic” cement (Premium Plus) into the construction market and has carried out significant research and development in the area of road construction in the Caribbean. The Soil Cement Stabilization technology has had successful trials in Trinidad and the next phase is to launch this technology throughout the Caribbean. This technology has many benefits to the road construction industry in terms of conservation of natural resources and cost savings.
Soil Cement Stabilization:
Soil stabilization is defined as the alteration of the physical and chemical properties of a soil mass to conform to the desired characteristics or the improvement of a less stable soil in both strength and durability. Most materials used for construction purposes often do not meet the required standards, both in performance-based tests conducted in the laboratory as well as in large-scale field tests. Therefore emphasis is needed for the development of mechanistic evaluation tests and techniques for stabilizing these materials.
The cement in Soil Cement Stabilization acts as a binder. Selecting the “optimal” cement content is now viewed more as a balancing act, in which the right amount of cement must be selected in order to achieve adequate strength and durability. Conversely, excessive cement contributes to wide shrinkage cracks and overly rigid bases which can produce continued cracking and faulting.
Soil Cement stabilization can be used in all aspects of Pavement construction as shown in Figure 1 below.
Figure 1: Various methods of soil stabilization with cement (PCA, 2010)
Cement Modified soil is defined as a soil treated with a relatively small proportion of cement in order to amend its undesirable properties so they are suitable for use in subgrade or foundation construction (i.e. drying, reducing plasticity), whilst a soil cement stabilized material is treated with a predetermined amount of cement to provide a strong, durable, weather resistant base.
Figure 2: Stabilization in the different layers of pavement’s structure (PCA, 2010)
- Enhanced load distribution
- Eliminates rutting of base
- Reduces moisture problems
- Reduces deflection
Fig 3: Distribution of wheel load on pavements
CONSTRUCTION OF CEMENT STABILIZED SOIL:
Typical construction Steps:
Advantages of Soil Cement stabilization: