Mechanical Properties and Seismic Performance Research on Primary-Secondary Structure for High-Rise Building

Primary-secondary structures have advantages on constructing high-rise buildings because of its superior structural performance and building adaptability, but systematic research on its mechanical properties and seismic performance is lacking. To solve the problem, mechanical properties of primary-secondary structures are studied under the support of the Major Program of National Natural Science Foundation of China (NSFC). The study reveals that primary-secondary structure exhibits the characteristic of two-level distribution of internal forces obviously under the vertical and lateral loads, and the internal force distribution of the secondary columns presents periodicity and replicability. We discuss the stiffness influence factors and find that the contribution of secondary structures to the overall stiffness is little but cannot be negligible. An effective simplified lateral displacement calculation method for primary-secondary structure considering shear and bending deformation is proposed.