Joint shear behaviour of reinforced concrete beam–column connections

Abstract

An extensive experimental database (341 cases in total) has been constructed for reinforced concrete (RC) beamcolumn connections subjected to quasi-static cyclic lateral loading. All cases within the database experienced joint shear failure, either in conjunction with or without yielding of beam reinforcement. RC joint shear strength models, which are applicable to both modern and older types of beam-column connections, have been developed using the constructed database in conjunction with a Bayesian parameter estimation method. Following this same procedure established to develop the strength models, joint shear deformation models (at maximum joint shear stress) have also been developed. The proposed quantitative RC joint shear strength and deformation models indicate that the following parameters are most important towards determining joint shear strength and deformation capacityconcrete compressive strength, beam reinforcement, joint transverse reinforcement, in-plane geometry, out-of-plane geometry and joint eccentricity. Finally, the influence of these six key parameters on the RC joint shear stress against joint shear strain behaviour at peak response has been assessed.

Capacity models for shear strength of exterior joints in RC frames: experimental assessment and recalibration

“…Table 2 reports some of the above mentioned parameters (i.e., the average quadratic error , the coefficient of determination R 2 , the reliability index β C and the average of V exp jh /V jh ratios) evaluated on the experimental results collected into the database as a whole. The numerical results show that the models by Hwang and Lee (2002) and Kim et al (2009) lead to the higher correlation. Moreover, the latter is characterised by the lower value of β C .…”

“…Furthermore, for EC8-compliant ones, the model by Sarsam and Phillips (1985) leads to the higher correlation, while the model by Hwang and Lee (2002) results in the lower average error. In terms of reliability measure, the model by Kim et al (2009) outperforms for under-reinforced joints, while the model by Bakir and Boduroglu (2002) is slightly more reliable for EC8-compliant one.…”

“…Regarding unreinforced joints, the models by Sarsam and Phillips (1985) and Hwang and Lee (2002) lead to the highest correlation. Moreover, the model by Kim et al (2009) leads to the highest correlation for the case of under-reinforced joints. Furthermore, for EC8-compliant ones, the model by Sarsam and Phillips (1985) leads to the higher correlation, while the model by Hwang and Lee (2002) results in the lower average error.…”

“…13 points out that the model under consideration tends to overestimate the steel stirrup contribution and underestimate the concrete one. Figure 14 compares the model by Kim et al (2009) and the corresponding experimental results. The graph shows a good correlation between theoretical predictions and experimental values for unreinforced, under-reinforced and EC8-compliant joints.…”

Simplified Model for Strengthening Design of Beam–Column Internal Joints in Reinforced Concrete Frames

“…Experimental joint failure databases (e.g., Kim [18] collected data on 341 subassemblies) highlight typical shear failures in conjunction with, but also without, yielding of longitudinal beam reinforcement. Influencing parameters for joint shear behavior are linked to key points on capacity curves displaying the most distinct stiffness changes.…”