Shear Strength Of Beam-column Joints Research Articles

Exterior RC joints subjected to monotonic and cyclic loading

PurposeThe purpose of this study is to develop two empirical models that predict the shear strength of exterior beam-column joints exposed to monotonic and cyclic loading using Gene expression programming (GEP).Design/methodology/approachThe GEP model developed for the monotonic loading case is trained and validated using 81 data test points and that for cyclic loading case is trained and validated using 159 data test points that collected from different 9 and 39 experimental programs, respectively. The parameters that are selected to develop the cyclic GEP model are concrete compressive strength, joint aspect ratio, column axial load and joint transverse reinforcement. The monotonic GEP model is developed using concrete compressive strength, column depth, joint width and column axial load.FindingsGEP models are proposed in this paper to predict the joint shear strength of beam-column joints under cyclic and monotonic loading. The predicted results obtained using the GEP models are compared to those calculated using the ACI-352 code formulations. A sensitivity analysis is also performed to further validate the GEP models.Originality/valueThe proposed GEP models provide an accurate prediction for joint shear strength of beam-column joints under cyclic and monotonic loading that is more fitting to the experimental database than the ACI-352 predictions where the GEP models have higher R2 value than the code formulations.

Finite Element Analysis of Beam – Column Joints Reinforced with GFRP Reinforcements

Glass Fibre Reinforcement Polymer (GFRP) reinforcements are currently used as internal reinforcements for all flexural members due to their resistance to corrosion, high strength to weight ratios, the ability to handle easily and better fatigue performance under repeated loading conditions. Further, these GFRP reinforcements prove to be the better alternative to conventional reinforcements. The design methodology for flexural components has already come in the form of codal specifications. But the design code has not been specified for beam-column joints reinforced internally with GFRP reinforcements. The present study is aimed to assess the behaviour of exterior beam-column joint reinforced internally with GFRP reinforcements numerically using the ABAQUS software for different properties of materials, loading and support conditions. The mechanical properties of these reinforcements are well documented and are utilized for modelling analysis. Although plenty of literature is available for predicting the joint shear strength of beam-column joints reinforced with conventional reinforcements numerically, but no such study is carried for GFRP reinforced beam-columns joints. As an attempt, modelling of beam-column joint with steel and with GFRP rebars is carried out using ABAQUS software. The behaviour of joints under monotonically increasing static and cyclic load conditions. Interpretation of all analytical findings with results obtained from experiments. The analysis and design of beam-column joints reinforced with GFRP reinforcements are carried out by strut and tie model. Strut and Tie models are based on the models for the steel reinforced beam-column joints. The resulting strut and tie model developed for the GFRP reinforced beam-column joints predicts joint shear strength. Joint shear strength values obtained from the experiments are compared with the analytical results for both the beam-column joints reinforced with steel and GFRP reinforcements. The joint shear strength predicted by the analytical tool ABAQUS is also validated with experimental results.

STRUCTURAL PERFORMANCE OF R/C EXTERIOR BEAM-COLUMN JOINT USING MECHANICAL ANCHORAGES

Mechanical anchorage has been developed as an answer to bent-anchorage problems recently, and the authors have proposed the design criteria on reinforcement detailing of R/C exterior beam-column joint. In this paper, the application of highstrength material is studied through various experiments, in which compressive strength of concrete, the effect of anchoragelength of beam reinforcement, depth of column, and the quantity of shear reinforcement in beam-column joint, are examined. Consequently, the authors clarify that proposed design formula can be applied for estimation of anchorage strength of beam reinforcement and shear strength of beam-column joint, as well as design criteria on structural performance of R/C exterior beam-column joint.

超高強度コンクリートを用いたRC柱梁接合部の構造性能

This paper reports the results of an experimental study on the structural performance of beam-column joints composed of ultra-high-strength concrete (cast-in-place or precast) with a compressive strength of more than 100N/mm^2 and longitudinal beam reinforcement with a yield strength of 685N/mm^2. A total of ten specimens were used, and joint configuration, column concrete strength and amount of longitudinal beam reinforcement were used as parameters. The study has revealed that the shear strength of beam-column joints and the bond strength of longitudinal beam reinforcement can be evaluated by using evaluation formulas currently in use. This paper also proposes a method for evaluating shear crack width in the serviceability limit state developed by examining the test results.