A review of specifications for lateritic materials for roads

Abstract

Most lateritic materials such as ferricretes, laterite or lateritic soils do not comply with traditional specifications for road pavement layers. This is a particular problem when materials are required for low volume roads and little else is available. However, experience with many lateritic materials has shown that they can be successfully used with specifications that are outside traditional requirements. A review of various specifications concluded that the specifications used in Brazil for national roads are probably those based on the most pertinent and detailed research, the earliest work on which was carried out in Angola and Mozambique. In this paper the wide range of specifications suggested internationally for lateritic materials is discussed and the properties of several lateritic materials successfully used in roads in various sub-Saharan countries are compared with the Brazilian specifications, suggested for interim use in southern Africa.