Non-linear FEA of mechanical properties of modular prefabricated steel-concrete composite joints

Abstract

This paper study the seismic performance of modular prefabricated SRC column to steel beam composite joint (MPCJ) under static loading. Numerical modeling of MPCJs with three different beam-end connections was carried out in ABAQUS. Results of the numerical calculation were compared with existing quasi-static test results to verify the feasibility of the numerical model. The model was then used to analyze changes in the moment-rotation relation, failure mode, ductility, stiffness, and bolt stress in the joint between the column and joint module. Besides, stress distributions in the joints were analyzed along different stress paths. Under monotonic loading, the mechanical performance of the MPCJ is significantly affected by the beam end connection mode. Failure of the MPCJ mainly occurs at the beam end connection, thus, the aim of keeping the plastic hinge away from the joint core and preventing shear failure is achieved. Furthermore, the maximum story drift ratio is 3.9–5 times greater than the recommended limit, which indicates good ductility and deformation performance. The MPCJ of the three-beam end connection methods is all semi-rigid connections. The beam end structure will have a large influence on the bolt tension and stress distribution. According to the test research results, a nonlinear model with three parameters including joint cover plate cantilever section length, flange connecting plate thickness and flange connecting plate weld length was established. The theoretical calculation results was consistent with the results of the numerical simulation. MPCJs can be designed based on the proposed theoretical calculation formula.