ANALELE UNIVERSITII “DUNREA DE JOS” DIN GALAI Fascicula II, Supliment A, anul XXIV (XXIX) 2006 92 ON THE POSSIBILITY OF USING THE SLAGS FROM IRON AND STEEL INDUSTRY IN ROAD CONSTRUCTION FROM THE POINT OF VIEW OF THEIR PHYSICAL-MECHANICAL PROPERTIES Licua NISTOR (CRISTEA) 1,2 , Antoaneta ENE 3 , Romana DRASOVEAN 3 1 SC DSU România SRL, Mittal Steel, 1 Smârdan, Galati 2 “Dunarea de Jos” University of Galati, Faculty of Sciences, Chemistry Section 3 “Dunarea de Jos” University of Galati, Department of Physics Abstract In this paper we present the types of slags resulted from the blast furnace and steel plants and the similarities of their physical and mechanical properties, obtained by mechanical processing after their slow cooling, with the natural rock aggregates used in mixtures composition and road concretes, as well as for the foundations layers. The implications of their exploitation for the environment are: the limitation of the deposited wastes volume and of the impact upon the natural equilibrium and landscape; the diminishing of the stockyard area, the diminishing of the neccesary of the mineral materials extracted from the litosphere; the limitation of the environment degradation by the location of extraction careers. The studied properties were: density, granule shape, shaping coefficient, 10% fine, water absorption, bitumen adherence, impact strength, compression strength, Los Angeles wear, frost-thaw resistance and elasticity module. 1. INTRODUCTION Slag is one of the main by-products of almost all metallurgical processes [1-8]. It is a non-metallic material which is produced together with the metallic products of these processes. This product is employed as certified material in road building [1,3-11], waterway stabilization [2], agriculture and in many other sectors. The using of these alternative materials helps to conserve primary raw materials and natural resources [11-13]. For many reasons steel slag has been used successfully in constructions for decades. One of them is the local availability. Furthermore it has certain advantages compared to natural stone: the high raw density coupled with the high abrasion resistance, the rough surface and the cubic shaped grain. In Europe 42% of slag is used in the construction of roads [1,2,7]. Steel slag that is used for hydraulic structures has to ensure - like natural aggregates - environmental compatibility, a sufficient volume stability and frost resistance as well as a high compressive strength [2]. Owing to [2] • careful selection • suitable process route • appropriate heat treatment • good processing a range of construction, agricultural and other products is formed for use in a large number of important applications. Iron- and steel making are high tech, well-controlled process operations which employ the most up to date methods of manufacture. All metallurgical products have to meet stringent specifications and acceptance criteria,