Effect of replaceable coupling beams on damage of frame-core structures

In order to facilitate the quantitative assessment on structural damage under rare earthquakes, the more practical seismic damage identification criteria for whole structures and components were given based on the domestic and international seismic design codes and related research results in this paper. The maximum instantaneous inter-story drift ratios, residual deformations and component maximum rotation angles can fully reflect the damage of the whole structure and various structural components, thus can be applied in the structural seismic design. According to the characteristics of shear deformation of the coupling beams, a new type of replaceable coupling beams was proposed, and the corresponding design method was given. The calculation results for a frame-core mixed structure example show that the effect of the replaceable coupling beams on the lateral stiffness of the structure is small, and the inter-story drift ratios and the corresponding damage of the structure under rare earthquakes are reduced by improving the energy dissipation capacity. With the use of replaceable beams, the damage degree on the shear walls of the core tube is obviously reduced, the residual deformation on the top of shear walls decrease remarkably. Although the deformation on the energy dissipation segment of replaceable beams is very large, the concrete beam segments connected to it are basically in elastic states. For the steel frame-RC core tube mixed structure, the frame columns and frame beams are less damaged under rare earthquakes, and the effect of the replaceable beams is small.