A procedure for generating performance spectra for structures equipped with passive supplemental dampers

Self Cite

Summary This paper presents a general framework for predicting the residual drift of idealized SDOF systems that can be used to represent non‐degrading structures, including those with supplemental dampers. The framework first uses post‐peak oscillation analysis to predict the maximum ratio of residual displacement to the peak transient displacement in a random sample. Then, residual displacement ratios obtained from nonlinear time‐history analyses using both farfield and near‐fault‐pulse records were examined to identify trends, which were explained using the oscillation mechanics of SDOF systems. It is shown that large errors can result in existing probability models that do not capture the influence of key parameters on the residual displacement. Building on the observations that were made, a general probability distribution for the ratio of residual displacement to the peak transient displacement that more accurately reflects the physical bounds obtained from post‐peak oscillation analysis is proposed for capturing the probabilistic residual displacement response of these systems. The proposed distribution is shown to be more accurate when compared with previously proposed distributions in the literature due to its explicit account of dynamic and damping properties, which have a significant impact on the residual displacement. This study provides a rational basis for further development of a residual drift prediction tool for the performance‐based design and analysis of more complex multi‐degree‐of‐freedom systems.

Section: Predictors For Maximum Sample Residual Ratiomentioning

confidence: 93%

Section: Residual Ratio Of Idealized Non-degrading Sdof Systemsmentioning

confidence: 99%

Section: Predictors For Maximum Sample Residual Ratiomentioning

confidence: 99%

Section: Predictors For Maximum Sample Residual Ratiomentioning

confidence: 99%

Section: Predictors For Maximum Sample Residual Ratiomentioning

confidence: 99%

See 3 more Smart Citations

A probabilistic framework for estimating the residual drift of idealized SDOF systems of non‐degrading conventional and damped structures

Guo¹,

Christopoulos

2017

Self Cite

Response prediction, experimental characterization and P‐spectra design of frames with viscoelastic–plastic dampers

Guo¹,

Christopoulos

2016

Self Cite

Summary Viscoelastic–plastic (VEP) dampers are hybrid passive damping devices that combine the advantages of viscoelastic and hysteretic damping. This paper first formulates a semi‐analytical procedure for predicting the peak response of nonlinear SDOF systems equipped with VEP dampers, which forms the basis for the generation of Performance Spectra that can then be used for direct performance assessment and optimization of VEP damped structures. This procedure is first verified against extensive nonlinear time‐history analyses based on a Kelvin viscoelastic model of the dampers, and then against a more advanced evolutionary model that is calibrated to characterization tests of VEP damper specimens built from commercially available viscoelastic damping devices, and an adjustable friction device. The results show that the proposed procedure is sufficiently accurate for predicting the response of VEP systems without iterative dynamic analysis for preliminary design purposes. A design method based on the Performance Spectra framework is then proposed for systems equipped with passive VEP dampers and is applied to enhance the seismic response of a six‐storey steel moment frame. The numerical simulation results on the damped structure confirm the use of the Performance Spectra as a convenient and accurate platform for the optimization of VEP systems, particularly during the initial design stage. Copyright © 2016 John Wiley & Sons, Ltd.

Influence of gravity connections and damper activation forces on the seismic behavior of steel CBF buildings with dissipative floor connectors

Paronesso

Lignos

2023

This paper investigates the influence of typical gravity connections on the seismic demands of steel concentrically braced frame (CBF) buildings with friction dampers as dissipative floor connectors. The investigated connections include (i) typical shear tab, (ii) clip angle, (iii) flush end‐plate and (iv) shear tab connections with bottom T‐stub. It is shown that the seismic behavior of the gravity framing system (GFS) is practically insensitive to the gravity connection type because the supplemental damping provided by the dissipative floor connectors dominates the seismic response of the GFS. While flush end‐plate and shear tab connections with bottom T‐stub generally exhibit smaller rotational demands than more flexible gravity connections, the resultant lateral drift demands in the GFS are more‐or‐less identical in all cases due to the elastic contribution of the gravity columns. A simplified method is proposed to evaluate the influence of the damper activation forces on the seismic response of multi‐story CBF buildings equipped with floor sliding friction dampers. First, the building is transformed into an equivalent single‐degree‐of‐freedom system. Subsequently, dual graphics called P‐spectra are generated through nonlinear response history analysis. These graphics allow to estimate the peak floor absolute acceleration demands and peak/residual roof displacements of the GFS as a function of the activation forces of the sliding friction dampers. An application example demonstrates that the proposed method can be reliably employed in a pre‐design phase to identify the range of damper activation forces through which an optimal performance of the steel CBF building may be anticipated.