Behavior of interior RC wide and conventional beam-column roof joints under cyclic load

• Roof wide and conventional beam-column joints were investigated under cyclic loads.
• Both of the specimens had almost equal energy dissipation capacity.
• In wide or conventional beam, bottom bars showed better bond behavior than top bars.
• Roof wide beam-column joint performed quite well in carrying lateral loads.
• Joint shear requirements can be relaxed for roof wide beam-column joints.

Performance of RC interior beam-column joints at roof level is defined as the area needing research by ACI 352R-02. Because of a lack of research data on performance of this type of joints, two half scale interior beam-column connections with discontinuous column were designed in accordance with ACI 318-11 and ACI 352R-02 provisions. One of the specimens had wide beams and the other had conventional beams to compare their behavior. These specimens were tested under quasi-static cyclic loading. It became clear by the experiments that roof wide beam-column joint had lower strength compared to that of roof conventional beam-column joint. Both of the specimens had almost equal energy dissipation capacity. The conventional beam-column joint reached its expected capacity but wide beam-column joint did not reach its capacity. Moreover, wide beam-column joint had sufficient joint shear strength unlike conventional one. Therefore, joint shear requirements could be relaxed for roof wide beam-column joint. This relaxation must be reapproved by more tests to be advisable for design purposes.