Developing Appropriate Roadbase for Bangladesh Pavements

In Bangladesh due to the shortage of stone aggregates, mixes of brick aggregates and fine sand are widely used for the construction of pavement foundations. The brick aggregates are weak in strength properties and degrade rapidly particularly in presence of moisture. Again, heavy rainfall and rising water table in the rainy seasons cause moisture saturation in the pavements due to lack of necessary drainability. This leads their faster deterioration and consequent premature failure, whether the pavement material is stone aggregate or brick aggregate, due to the development of high pore water pressure under the moving wheel loads. Many pavements are also vulnerable to recurrent floods, once in every few years, and simply washed away. In this research work, use of cement stabilized brick aggregate-sand-soil mixes as roadbase material has shown satisfactory results both in laboratory investigation and trial construction. A primary assessment has indicated that the mixes are also considerably cheaper than the conventional stone aggregate roadbase mix.