Introduction

It has been estimated that approximately 50 million tons of concrete are currently demolished each year in the European Economic Communities (1). Lindsell and Mulheron (87) have estimated that 11 million tons of demolished concrete are dumped at landfill sites each year in the United Kingdom. Equivalent figures are 60 million tons in the United States (2, 3), and in Japan (12) the total quantity of concrete debris available for recycling on some scale is about 10 to 12 million tons. Karaa (93) has estimated that approximately 13 million tons of concrete is demolished in France every year. Very little demolished concrete is currently recycled or reused anywhere in the world. Hie small quantity which is recovered is mainly reused as nonstabilized base or sub-base in highway construction. The rest is dumped or disposed of as fill.