Use of laminated mechanical joints with metal and concrete plates for precast concrete columns

This study investigated the structural behavior of a mechanical joint with laminated concrete and metal plates for moment connections which can be used for the rapid erection of reinforced concrete precast columns. A concrete filler plate was placed between the metal column plates to transfer loads and protect nuts threaded with rebars. Nonlinear numerical finite element analyses considering concrete damaged plasticity was also performed to evaluate the load–displacement relationship, plate deformation of the joints with concrete filler plates, and rates of strain increase of the structural components. The influence of the column and concrete filler plates on the rate of strain increase of the structural components attached to the column plates was explored to determine how concrete, rebars, and steel sections, were activated relative to the stiffness of the metal plates. The strain values of structural elements that were attached to plates with sufficient stiffness values were found to be higher than those of the structural elements that were attached to plates with smaller stiffness values. These strains were evident in the nonlinear finite element analyses and experimental investigations. It can be inferred that laminated mechanical plates consisting of metal and concrete plates can be implemented and used to replace conventional precast connections.