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Integrating the concepts of frictional energy dissipation and low-damage mechanism, this paper proposes a built-in continuous-column (BCC) steel moment frame structure with low-damage cover plate slip-friction connections (CPSFCs) at the column bases. The slip-friction connections can convert the buckling energy dissipation of the column into frictional energy dissipation, and the continuous column can improve the lateral deformation mode of the structure under seismic action. The strength and stiffness deterioration characteristics of the material were considered in the simulation of the seismic performance of the structure, and the simplified numerical models of CPSFCs and continuous columns were established in OpenSees. Comparative analyses were carried on a seven-story steel frame, steel moment frame (SMF) with CPSFCs at the column bases (CPSFC–SMF), and a built-in continuous column steel frame (BCCF) with CPSFC at the column bases (CPSFC–BCCF). The results showed that CPSFC slightly reduced the bearing capacity of the steel moment frame but minished the structural stiffness degradation and increased the ductility of the structure. The setting of CPSFC changed the plasticity hinge sequence of the structure, resulting in a homogeneous deformation between stories. The CPSFC–BCCF had the best damage pattern and the most uniform inter-story energy dissipation.

Based on the concept of structural damage control, a beam-through steel frame system with continuous columns was constructed. Replaceable connectors were set at both ends of an H-shaped steel column to connect the beam with high-strength bolts. In this study, three specimens were designed and fabricated, that is, a standard H-shaped column, an H-shaped column with replaceable connectors at the bottom of the column, and an H-shaped column with replaceable connectors at both ends. Low-circumferential reciprocal loading tests were carried out to analyse the influence of the location of replaceable slip friction joints on the seismic performance of steel columns. Results showed that the H-shaped steel column with replaceable slip friction joints at both ends slipped during the loading process, as expected. The test hysteresis curve was full, and the skeleton curve did not drop significantly; thus, the column demonstrated satisfactory seismic performance. The steel column was not significantly damaged or deformed, and connectors could be reset and replaced after an earthquake to achieve post-earthquake repair. The effect of the thickness of the horizontal limbs of the connectors on the seismic performance of the H-shaped column with replaceable connectors at both ends was analysed using finite element simulation. The results revealed that the reasonable setting of the thickness of the horizontal limbs of the connectors can ensure the frictional energy dissipation capacity of the connectors and achieve the expected damage control.

This paper proposes a new type of steel slip-friction column base connections with arc end-plates. Two arc end-plates of the steel column base, which can slide between each other to some extent, were set at the position where the column base is subject to plastic deformation. Thus, the sliding-friction energy dissipation between the arc end-plates can effectively minimize or eliminate the energy dissipation of the traditional column base connections. Cyclic loading tests were conducted to study the hysteretic performance and energy consumption performance of the proposed connections. Considerations have been given to different axial compression ratios, Belleville springs (Bes), brass plates, and horizontal loading protocols. The test results show no obvious deformation or damage during the radial cyclic loading test. The curve shape of the test measurement approximates a parallelogram, showing good force performance. The proposed connections with the increasing axial compression force can increase the energy dissipation ability and load-carrying capacity. Therefore, the proposed connection has perfect seismic behavior.