Comprehensive approach to evaluation of mechanical properties of waste aggregate concrete reinforced by steel fiber

Waste aggregate concretes are playing a more and more important role in construction industry. Over the last decade, their application has evolved from very basic pavements and elements with limited mechanical characteristics to full scale structures and large pre‐cast beams and slabs. In some cases, steel fiber was used as the only reinforcement of such elements. The application of steel fiber was based on the assumption that the influence of dispersed reinforcement would be the same as it was in ordinary concrete. Therefore, both technologies of preparation of such concrete and volumes of added fiber were the same as in ordinary concrete. In authors’ opinion, concrete based on waste aggregate creates much more complex environment for fiber reinforcement than traditional cement matrix. Recognizing the need of comprehensive approach to this problem, authors conducted a thorough research program. Concrete based on waste red ceramic aggregate was modified by different volumes of varied engineered steel fiber. Conducted tests covered full mechanical characteristics. Strength classes according to fib model code were assigned to tested fiber concretes. The best mixes were pointed out.