Ultimate Moment of Reinforced Concrete Interior Beam-Column Joint

Abstract

This paper extends a kinematic model named nine DOF model proposed by one of the authors which could predicts the moment capacity and moment at balanced failure of reinforced concrete beam-column joints. The original model is applicable to interior beam-column joints of which the geometric and loading conditions are equal and symmetric about a diagonal line of the joint. The extension reduced the limitations and allows for different sectional dimensions and reinforcement of beam and column and different forces on the beams and columns. The results from the extended model compared to experimental results and the model gave accurate prediction.

Effect of Geometric Parameters on the Behavior of Eccentric RC Beam–Column Joints

“…Ma et al [20] and Wong et al [21] reported that increasing the joint reinforcement helped to improve the plastic deformation capacity and delay the joint deterioration. Goto and Joh [22] and Kusuhara et al [11] have noted the same results with increased shear reinforcement at the joint region. It was also found that slab reinforcement helps to move the acting line of the resultant force away from the flush face, thus reducing the torsional demand caused by eccentricity [10,14,17,20].…”

“…Moreover, the post-peak segment of the interior joints became steeper as the joint aspect ratio increased. This can likely be attributed to the out-of-plane moment of the beams [1,11], as shown in Figure 15b, that reaches around 14.5%, on average, of the in-plane flexural moment measured at the same section, resulting in a decrease in the joint panel confinement by the beams [94]. Overall, the interior joints have inferior performances, with the maximum loads lower by 25% than the exterior ones.…”

“…The effect of joint eccentricity and other geometrical properties on the behavior of RC beam-column joints subjected to reverse-cyclic lateral loading has been examined [8][9][10][11][12][13].…”

“…In the early 1990s, Joh et al [8], Lawrance et al [9], and Raffaelle and Wight [13] observed early loss of strength and low ductility of cruciform eccentric beam-column joints due to the noticeable development of torsional cracks. Kusuhara et al [11] demonstrated the effect of out-of-plane and torsion moments leading to a nonsymmetric yielding in beam reinforcement. Matsumoto et al [14] emphasized that the reduction in shear strength of eccentric joints could be minimized with an eccentricity ratio, which is the ratio of the beam shift distance to the column width, below 0.25.…”

Experimental Assessment of RC Frame Seismic Performance with Different Slab Types

“…Acknowledging the pivotal significance of comprehending the dynamics of these subassemblies, numerous experimental works have been undertaken with a specific focus on elucidating the behavior of external or internal beam-to-column joints subjected to cyclic loading (Abdel-Fattah & Wight, 1987;Kusuhara et al, 2004;Lu et al, 2012;Paulay et al, 1978;Vollum & Newman, 1999). Previous studies frequently featured test subassemblies that comprised connections involving main beams without a slab component.…”