ON SITE BEHAVIOUR OF INTERFACE SYSTEMS

This paper deals with the results of an evaluation of different sites in Belgium where interface systems were used for the prevention of reflective cracking. The selected projects concern asphalt overlays on cement concrete slabs where SAMI, non-woven geotextiles impregnated with modified bitumen, grids and steel reinforcing nettings were used as interface systems. Depending on the project, the reparations were executed very recently to ten years ago. The aim of this evaluation is twofold. Firstly, to evaluate and to improve the lying procedures of the different products and secondly to evaluate their long-term performance. The first part of the paper describes a recently constructed experimental road where a SAMI, an impregnated nonwoven, a grid and steel reinforcing nettings were applied. In these experimental sections, the lying techniques of these different products that were introduced recently in the Belgian standard tender specifications could be involved. In a second part of the paper, the results of visual inspections of different sections, performed at regular time intervals, are reported. They give insight in the reasons of failure of certain projects and on the long-term performance of these techniques. Most of the projects were already evaluated for the previous RILEM-conferences on reflective cracking; these results are completed with the latest information of evaluations. For the covering abstract see ITRD E109276.