Dynamic model, performance analysis and evaluation of frame-distributed rocking-core tube structure

Abstract

To obtain adequate lateral stiffness for frame-core tube (FCT) structures, the core tube area proportion is often increased and/or overly reinforced which often limits the layout flexibility and economy of the structure. A new high-rise configuration named frame-distributed-core tube (FDCT) is proposed to reduce the tube area proportion of the FCT structure. Combined with a rocking system, the frame-distributed rocking-core tube (FDRCT) structure is further proposed, which aims to reduce the damage caused by soft-stories due to by the weakening of the stiffness of the FDCT structure. Simplified models are built, and the structural dynamics are derived based on the Lagrangian equation. Through numerical simulation of three structures under ground motions, it is shown that the FDRCT structure has good energy dissipation and damping performance. The inter-story drift ratios of the structure decreases with the increase of the distributed rocking tubes mass. Under different site conditions and long-period ground motions, numerical simulations and shaking table tests show that the distributed rocking tubes can effectively reduce the structural response and improve the seismic performance. The FDRCT configuration gives better damping performance under long-period ground motions. A performance-profit evaluation shows that the proposed high-rise structure system of FDRCT provides a safe and cost-effective design solution.