Analysis on mechanical properties of exposed column-base plate weak-axis connections with different anchor bolt layouts

To investigate the mechanical properties of exposed column-base plate weak-axis connections with different anchor bolt layouts, taking anchor bolt diameter, anchor bolt position and base plate thickness as parameters, seven full-scale exposed column-base plates were designed and tested under low-cycle lateral reversed cyclic loading. The typical failure modes of specimens were defined, as well as the flexural rigidity, ductility, and energy dissipation capacity of specimens were investigated. The test results show that the exposed column-base plate with anchor bolts can be considered as semi-rigid connections, and it has favorable ductility and energy dissipation capacity. Furthermore, the bolt diameter, the thickness of base plate and the height of the stud welding should be designed accordingly to prevent brittle failure. Compared with the internal layout of the anchor bolt, the external layout can increase the flexural bearing capacity of the exposed column-base plate connections, but the ductility will be reduced. In addition if the diameter of the anchor bolt are increased, the flexural bearing capacity of the exposed column-base plate connections with anchor bolt internal layout will be improved. The finite element model was used to analyze the stress in the typical failure parts of different specimens as well as the parametric analysis was carried out to investigate the influence of different parameters on the flexural behavior of exposed column-base plate connections. The simulation result shows that the column-base plate connections with different anchor bolt layouts are more sensitive to the axial compression ratio and anchor bolt diameter, and its flexural bearing capacity varies by more than 20%. Compared with the external ones, the internal layout is more sensitive to the three types of parameters: the anchor bolt distance in the strong axis, the anchor bolt distance in the weak axis, and the thickness of the base plate. The bearing capacity of internal layout varies more than the external layout ones. © 2021, Editorial Office of Journal of Building Structures. All right reserved.