J.KNAPTON AND H.MURAT ALGIN University of Newcastle upon Tyne

The growth in the international usage of flexibly bedded pavers since World War II has brought about the need fully to understand how pavers bedded in sand function. The design methods are based on the concept of making pavers and their bedding sand equivalent to conventional pavement construction materials. Experience has shown that pavers do not behave as a collection of individual units but rather interlock so that they behave in a manner close to that of flexible materials. A way in which pavers dissipate stress applied by rolling loads has been investigated and an understanding of the interlock process thereby developed. The paper explains the theoretical analysis and demonstrates how it can be used to establish the nature and value of interlock. It shows how patch loading on the surface of pavers produces patterns of stress within the bedding material and how these patterns develop as a patch loading rolls across pavers. The results are being used in the development of paver jointing systems and it is now possible to assess more effectively the tolerances required in paver installation.