Experimental Investigations of Reinforced Concrete Beams with Innovative Truss-Shaped Reinforcement System

The purpose of the work is an experimental analysis of the behavior of reinforced concrete beams with a new, patented system of truss-shaped reinforcement. Experimental tests of reinforced concrete beams with conventional reinforcement and with truss-shaped, mass equivalent reinforcement, with two different values of longitudinal reinforcement ratio, were carried out. The testing results of the load-carrying capacity and displacements of beams are presented. The cracking and failure mechanism of beams with a new truss-shaped reinforcement system was also analyzed. The test results for conventionally reinforced beams and with truss-shaped reinforcement were compared. The test results show that the use of the truss reinforcement has an influence on increasing the load-carrying capacity of beams. The amount of this increase depends on the total longitudinal reinforcement ratio and reaches as much as 95% for beams with a low reinforcement ratio and 12% for beams with a higher reinforcement ratio. Based on the investigation of the cracking mechanism, it can be concluded that the failure of the beams with transverse truss-shaped reinforcement occurs with a greater number of smaller cracks, which are more evenly distributed along the length of the cracking zone, and have a shorter range over the cross-section depth, which results in their smaller opening widths. The comparative analysis shows the effectiveness of the proposed reinforcement system, justifying the high potential possibilities of its use for the reinforcement of concrete structural elements.