ALT-MAT-project, Finnish national report

The environmental aspects strongly necessitate more extensive utilisation of the alternative materials.This utilisation needs more information of the mechanical and leaching properties, functional requirements and long term stability of the materials.The European ALT-MAT project defines methods by which the suitability of alternative materials for use in road construction can be evaluated under appropriate climatic conditions.The Finnish national work in ALT-MAT project concentrated on the development of the climate chamber test.The purpose of these test was to simulate the field conditions of road structures (miniembankment) without a pavement.The test consisted of 20 wetting-drying and freezing-thawing cycles.Miniembankments were wetted with salt solution.The leaching of contaminants due to these accelerated climatic cycles and salt solution was studied.The tested materials were two slags: ferrochrome and blast furnace slag.The test results exhibited that the leached amounts of many metals were very low, usually below the limit of detection.These results were verified with other leaching test results.All test data showed that the leaching of contaminants for both slags is very moderate.The climate chamber test proved to be a good, but expensive method to test the environmental suitability of alternative materials.