Finite element analyses on energy dissipation capacity of upper flange welded-lower flange bolted beam-column connection with slotted holes

In steel structures, the greater energy dissipation capacity of a beam-column connection means greater seismic performance. Increasing energy dissipation of the slip of cantilever beam splices is an effective method of improving the energy dissipation capacity of beam-column connections. This paper provides a study of an "upper flange welded-lower flange bolted" (UWLB) beam-column connection with slotted holes. The UWLB connection is a new type of the beam-column connection, whose upper flanges and lower flanges of the splicing area have different splicing methods, the upper flanges welded while the lower flanges bolted. Six finite element models were established to analyze the effects of the different slotted hole dimensions on energy dissipation capacity. The results show that the energy dissipation of the splicing area increases with the increase of slotted hole dimensions, and the connections have greater rotational capacity. The energy dissipation ratio of the splicing area is more than 37.7%, the ratio increases with the increase of the slotted holes dimensions. The UWLB connections with slotted holes achieved 0.06 rad rotation under the cyclic loading. The UWLB connection with slotted holes has greater rotational capacity and higher energy dissipation capacity of the splicing area than the normal UWLB connection.