ABSTRACT
The continued demand for aggregates in highly-developed countries has now resulted in shortages of stone and gravel in many localities, e.g. in large urban areas where aggregate availability has traditionally been low and/or where the production of aggregates is prohibited for environmental reasons. In many developing countries the availability of good cheap supplies of aggregates is limited and is not able to keep up with the needs of their burgeoning economies. As a consequence, greater attention is now being paid to the use of locally-available substitute materials such as stabilized soils (and 'waste' materials — see Chapter 5) to meet road construction needs.
