Impact of recycled aggregates on selected physical and mechanical characteristics of cement concrete

Abstract

The issue of using construction rubble was recognized in Europe not earlier than in the nineties of the twentieth century. This was due to economic and ecological considerations. However, recycled aggregate is characterized by high volatility of physical and mechanical properties. The quantity and type of various kinds of impurities harmful to the durability of concrete is virtually unpredictable. For over twenty years various organizations in different countries have tried to sort out this problem and possibly unequivocally define the criteria for the suitability of different types of recycled aggregates to the production of concrete. The article presents and compares the most important guidelines, currently in force, regulating the scope of use of recycled aggregates (RILEM as well as Japanese, German and European standards). The article also contains the results and the analysis of comparative studies of selected physical and mechanical characteristics of concrete produced with the use of natural aggregate and concrete produced with the use of recycled aggregate obtained from milling of masonry.