Experimental study and numerical simulation analysis of RCS joint with asymmetric friction connection

Based on the seismic design principle of recoverable function and replaceable seismic design, a novel type of reinforced concrete column-steel beam (RCS) joint was proposed, incorporating an asymmetric friction connection in the lower flange of the steel beam. Subsequently, experimental tests, numerical simulations, and theoretical analyses were conducted to evaluate this joint. The test results indicate that the RCS joint with asymmetric friction connection can effectively exert friction slip energy dissipation characteristics, demonstrating good seismic performance in terms of bearing capacity and stiffness. The damage observed in the specimen is primarily focused on the spliced cover plate of the steel beam, with minimal deformation in the core area of the joint. Numerical simulation and parameter analysis were conducted using ABAQUS software. The results demonstrate that the finite element model accurately reproduces the observed phenomena in the test. The parameter analysis reveals that a 10 % increase in bolt preload or a 0.05 increase in friction coefficient can result in a 7 % or 13 % rise in joint bearing capacity, respectively. Finally, a calculation method for determining friction slip in RCS joints with asymmetric friction connection was developed, showing close agreement between the calculated results and finite element outcomes, indicating the accuracy of the formula.