The Australian road network is deteriorating as it ages past its original design life, due to lack of adequate maintenance and increasing axle loads. Remedial treatments such as recycling using treatment with mixes of bitumen emulsion, lime and cementitious products (ELCs) are being used to keep the road infrastructure intact. As with all new processes there are few guidelines for laboratory evaluation of treated materials or prediction of field performance. If the recycled pavement is designed with due investigation, research and an understanding of the basic performance characteristics, then structural performance can be enhanced. Environmental benefits are also obtained and a more economical pavement produced. This paper outlines some difficulties which may be encountered when designing pavements treated with ELCs and provides some general suggestions which may assist the engineer. Reference is made to the successful use of granular emulsion mixes (GEMS) in South Africa, and also to recent recycling programs by Queensland Transport, in Southern Queensland using cement and bitumen emulsion blends. (A)
Samenvatting