Abstract
Rocking post-tensioned steel frames capitalise on the use of rocking joints, and unbonded post-tensioning strands to provide self-centring action. Investigations on the complex and unconventional nonlinear dynamics of tied rocking steel frames, exclusive of supplemental damping methods, are presently limited. Increasing levels of energy-dissipation reduce the probability of observing nonlinear dynamic phenomena such as co-existing (high/low) amplitude responses at and around the system's nonlinear resonance. To this end, a finite element (FE) modelling framework is presented, validated and extended to multi-storey steel buildings. It is shown that the simulation strategies proposed enable an accurate representation of the complex nonlinear dynamics of self-centring structures, over a wide range of excitation frequencies and amplitudes. The methodology, applied to multi-storey steel frames, captures the presence of sub-harmonic resonances and higher-modes. It is also demonstrated that the additional demands observed in the rocking columns are the consequence of the asymmetry of the member boundary conditions.
Original language | English |
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Pages (from-to) | 826-837 |
Number of pages | 12 |
Journal | Soil Dynamics and Earthquake Engineering |
Volume | 115 |
Early online date | 29 Oct 2018 |
DOIs | |
Publication status | Published - 1 Dec 2018 |
Bibliographical note
Publisher Copyright:© 2018 Elsevier Ltd.
Keywords
- Finite-element
- Nonlinear dynamics
- Post-tensioned moment frame
- Rocking
- Self-centring