Sustainable Seismic Performance of Diagrid Core-Tube Structure with Replaceable Steel Coupling Beam

Abstract

The diagrid core-tube structure has been widely used in high-rise buildings in recent years, but there are few studies on the sustainable energy dissipation measures and seismic performance improvement of such structural systems. Because the coupling beam is the element connecting the inner tube and the outer tube in the diagrid structure, it is the first seismic defense line and an important energy-dissipation member in the seismic design of the overall structure. Therefore, this paper replaces the traditional reinforced concrete coupling beam of the inner tube of the shear wall with a replaceable energy-dissipation steel coupling beam, and the strength, stiffness, and stability of the replaceable steel coupling beam are designed to improve the sustainability of the structure. By changing the position of the replaceable coupling beam, the relative stiffness of the inner and outer tubes of the diagrid tube structure, and the plane form of the structure, the static elastoplastic analysis and seismic response energy analysis of different diagrid tube structures are carried out, and the influence of the replaceable coupling beam on the sustainable seismic performance of the diagrid tube structure is studied. The results show that the replaceable coupling beams have little effect on the ultimate bearing capacity of the structure, but the ductility and sustainability of the structure are significantly improved, and the whole building layout is the optimal layout scheme. The setting of replaceable coupling beams makes the diagrid tube structure show hysteretic energy-dissipation earlier under the action of large earthquakes, and the proportion of hysteretic energy-dissipation is greatly improved, which reduces the inter-story drift ratios and the damage degree of the diagrid columns under the action of large earthquakes. When the relative stiffness of the outer tube of the diagrid tube structure is small or the plane form of the structure is a regular quadrilateral, the application of replaceable coupling beams is more effective in improving the ductility and sustainability of the structure and reducing the damage to the diagrid column under large earthquakes.