Achieving enhanced seismic resilience in modern high-rise buildings requires advanced
structural systems capable of controlling damage from both first-mode and higher-mode
responses. This study develops a preliminary design procedure for a novel dual-mechanism
system that allows the uncoupling of overturning and lateral responses at the base of high-rise buildings. The system combines both rocking and shear mechanisms to mitigate higher-mode effects. By developing the design procedure, the study aims to facilitate the broader
adoption of the system to improve the seismic resilience of high-rise buildings.
To support the development of this procedure, a simplified numerical model was created to
represent the seismic behaviour of the uncoupled dual-mechanism system. After
establishing the ranges of key design parameters governing the system's strength and
component dimensions, a series of parametric studies were conducted using nonlinear
response history analyses for two seismic locations: Los Angeles in the United States and
Vancouver in Canada. Seismic performance spectra were generated based on these analyses
to guide the development of a preliminary design procedure for practical engineering
applications.
The parametric study established that for buildings up to approximately 300 m in height, a
practical range of geometric and strength parameters exists to successfully limit maximum
inter-story drift ratios to 1.5%, while controlling base displacements to a feasible 800 mm.
Beyond this height, it was found that the required dimensions of the rocking mechanism
components become impractically large for constructability and cost-effectiveness,
defining the system's effective application limit.
