Experimental tests of reinforced concrete beams with hybrid nodes and characterization of the results

Abstract

This research presents the study of the behavior of reinforced concrete beams with hybrid nodes based on a 23 factorial experiment design, whose independent variables are: shear moment ratio (M/V), ratio between the height of the node and the depth total of the reinforced concrete beam (hc/h) and the use of suspension stirrups. A test of eight types of specimens was performed with one replicate, for a total of sixteen specimens, plus four control specimens without knots. The tests show that the region disturbed by the joint should not be used for the bending theory of beams. The disturbance generates a decrease in the sectional resistance, which can be compensated with the suspension stirrups, which help to control cracking and transfer the efforts from the tension zone to the compression zone, with a significant increase in resistance.