Failure area evaluation of the coupler with threaded bar: Experimental and Numerical study

The problem of overcrowding at the junction of the rebars is very significant, particularly for seismic details. Mechanical couplers can, thus offer an appealing solution that eliminates the disadvantages of traditional reinforcement splicing. By identifying the target area for bar failure, the potential area for failure could be modified with this in mind, it is very useful in assessing the position of the reinforced concrete (RC) plastic hinge. In this context, the present study focuses on the numerical and analytical modelling of the experimentally obtained response of Integrated bar (without coupler) and bars with mechanical coupler to tensile uniaxial tests. Simulation results showed agreement with the experimental response in terms of load–elongation curve, Von Mises yield and failure mode .After validating the model, alternative designs (diameter, height and thickness of mechanical couplers and bar) were numerically tested to study the influence of the geometry of the structural system on the failures mechanical coupler. Overall results indicated that the optimum design would be the one with an increased diameter in the thread area of both the bar and the mechanical coupler. For this improved configuration, the load-bearing capacity was Similar to the Integrated bar (without coupler) Cases.