DTU Stabilised Soil Research Progress Report: SSRPR02 - How does cement stabilisation work?
D E Montgomery, (Oct 1998)
After a brief study of some relevant texts documenting the production, characteristics and use of Portland cement a better understanding of its cementitous qualities has been gained. The bonding of cement is caused by the hydration of the cement particles which grow into crystals that can interlock with one another giving a high compressive strength.
In order to achieve a successful bond the cement particles need to coat most of the material particles so that upon hydration a crystalline structure is created throughout the mixture of particles. Particle intimacy is important to ensure a good number of cementitic bonds between adjoining particles and this can be helped by mixing the cement into a mixture of particles with a good size distribution. The water in the mixture needs to be monitored to guarantee sufficient hydration of the cement and also to ensure adequate workability of the mix. Too much water will leave voids in the mixture after the water has evaporated off and will reduce the final set strength of the material.
The limitations to cement besides the careful control of materials and moisture are that cement requires time to fully cure and that it is susceptible to chemical attack. Never-the-less it is a highly suitable method of stabilisation and can easily be applied to stabilise a moderate variety of different soils for use in making building materials.
