Strengthening of edge reinforced concrete beam to column connections

One of the most common mistakes made in our country in the construction of reinforced concrete ?column+beam? systems is the discontinuity of the column stirrups inside the column-beam intersection region. During earthquakes, the formation of hinges at these weak regions of the nodes may cause total or partial collapse of the structure. This situation is more important especially at the edge column-beam intersection regions. The column tips not encircled at least at one of its faces, split from the beams bottom/top surfaces due to the lack/absence of stirrups at the nodes. This behavior is also observed in interior columns with insufficient or not proper stirrups. No other extensive study on this issue is found, as the repair/strengthening studies in our country are generally focused on structural members (column, beam, shear wall, etc.). Not many extensive and applicable studies are found in the literature. On the other hand, the number of collapsed or damaged buildings because of this issue is not negligible. Thus, an extensive experimental study focused on the strengthening of corner column-beam connections was planned. In this study, an edge column-beam connection was considered together with the slab and the beams attached in the transverse direction. Also, all of the forces at the member ends (shear force axial load and bending moment) caused by earthquake and vertical loads were generated using a new loading system. In this manner the study differs from other studies too. In strengthenings it was especially taken care of using native and cheep materials. Mainly 7 strengthening techniques were investigated. 23 specimens with a scale of ½ were tested. At the result of the study for the strengthening of beam to column connection, several effective, easy, applicable and cheep methods were developed.