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Effect of damping and yielding on the seismic response of 3D steel buildings with PMRF.

Reyes-Salazar A, Haldar A, Rodelo-López RE, Bojórquez E - ScientificWorldJournal (2014)

Bottom Line: The results show the limitations of the commonly used static equivalent lateral force procedure where local and global response parameters are reduced in the same proportion.It is concluded that estimating the effect of damping and yielding on the seismic response of steel buildings by using simplified models may be a very crude approximation.Much more research is needed to reach more general conclusions.

View Article: PubMed Central - PubMed

Affiliation: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Ciudad Universitaria, 80040 Culiacán, SIN, Mexico.

ABSTRACT
The effect of viscous damping and yielding, on the reduction of the seismic responses of steel buildings modeled as three-dimensional (3D) complex multidegree of freedom (MDOF) systems, is studied. The reduction produced by damping may be larger or smaller than that of yielding. This reduction can significantly vary from one structural idealization to another and is smaller for global than for local response parameters, which in turn depends on the particular local response parameter. The uncertainty in the estimation is significantly larger for local response parameter and decreases as damping increases. The results show the limitations of the commonly used static equivalent lateral force procedure where local and global response parameters are reduced in the same proportion. It is concluded that estimating the effect of damping and yielding on the seismic response of steel buildings by using simplified models may be a very crude approximation. Moreover, the effect of yielding should be explicitly calculated by using complex 3D MDOF models instead of estimating it in terms of equivalent viscous damping. The findings of this paper are for the particular models used in the study. Much more research is needed to reach more general conclusions.

Show MeSH
Local damping reduction factor for element forces, Model SC1.
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fig5: Local damping reduction factor for element forces, Model SC1.

Mentions: The damping reduction factors for local response parameters (RζL,SAC) are considered next. Typical values of RζL,SAC for axial loads and bending moments on selected members (Figure 1(c)) of Model SC1 are given in Figure 5. The results are similar in one sense to those of global response parameters but different in another: the RζL,SAC values significantly vary from one earthquake to another and from one interstory to another; the damping reduction factors, however, seem to be smaller for local response parameters, particularly for axial loads; values lower than 0.20 are observed in some cases for the 0–2 damping range, implying a response reduction larger than 80%. The variation of RζL,SAC from one column to another generally decreases as damping increases and it is smaller for bending moment than for axial loads.


Effect of damping and yielding on the seismic response of 3D steel buildings with PMRF.

Reyes-Salazar A, Haldar A, Rodelo-López RE, Bojórquez E - ScientificWorldJournal (2014)

Local damping reduction factor for element forces, Model SC1.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4109077&req=5

fig5: Local damping reduction factor for element forces, Model SC1.
Mentions: The damping reduction factors for local response parameters (RζL,SAC) are considered next. Typical values of RζL,SAC for axial loads and bending moments on selected members (Figure 1(c)) of Model SC1 are given in Figure 5. The results are similar in one sense to those of global response parameters but different in another: the RζL,SAC values significantly vary from one earthquake to another and from one interstory to another; the damping reduction factors, however, seem to be smaller for local response parameters, particularly for axial loads; values lower than 0.20 are observed in some cases for the 0–2 damping range, implying a response reduction larger than 80%. The variation of RζL,SAC from one column to another generally decreases as damping increases and it is smaller for bending moment than for axial loads.

Bottom Line: The results show the limitations of the commonly used static equivalent lateral force procedure where local and global response parameters are reduced in the same proportion.It is concluded that estimating the effect of damping and yielding on the seismic response of steel buildings by using simplified models may be a very crude approximation.Much more research is needed to reach more general conclusions.

View Article: PubMed Central - PubMed

Affiliation: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Ciudad Universitaria, 80040 Culiacán, SIN, Mexico.

ABSTRACT
The effect of viscous damping and yielding, on the reduction of the seismic responses of steel buildings modeled as three-dimensional (3D) complex multidegree of freedom (MDOF) systems, is studied. The reduction produced by damping may be larger or smaller than that of yielding. This reduction can significantly vary from one structural idealization to another and is smaller for global than for local response parameters, which in turn depends on the particular local response parameter. The uncertainty in the estimation is significantly larger for local response parameter and decreases as damping increases. The results show the limitations of the commonly used static equivalent lateral force procedure where local and global response parameters are reduced in the same proportion. It is concluded that estimating the effect of damping and yielding on the seismic response of steel buildings by using simplified models may be a very crude approximation. Moreover, the effect of yielding should be explicitly calculated by using complex 3D MDOF models instead of estimating it in terms of equivalent viscous damping. The findings of this paper are for the particular models used in the study. Much more research is needed to reach more general conclusions.

Show MeSH