Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames
The seismic response of structures is always influenced by second order (<i>P</i>–Δ) effects. The importance of these effects becomes significant when the structure experiences large plastic deformations. Seismic codes indicate that <i>P</i>–Δ effects may be counteracted by m...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-02-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/13/2/321 |
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| author | Francesca Barbagallo Melina Bosco Andrea Floridia Edoardo M. Marino Pier Paolo Rossi |
| author_facet | Francesca Barbagallo Melina Bosco Andrea Floridia Edoardo M. Marino Pier Paolo Rossi |
| author_sort | Francesca Barbagallo |
| collection | DOAJ |
| description | The seismic response of structures is always influenced by second order (<i>P</i>–Δ) effects. The importance of these effects becomes significant when the structure experiences large plastic deformations. Seismic codes indicate that <i>P</i>–Δ effects may be counteracted by means of an increase of the lateral strength required by a first order analysis, but the expressions of the Strength Amplification Factor (SAF) given in codes are often criticized by researchers. This paper proposes and validates a formulation of the SAF for Moment Resisting Frames (MRFs), which is a generalization of that derived in the past by some of the authors based on the response of SDOF systems. To this end, in a first stage of the research a set of steel MRFs is designed and analyzed neglecting <i>P</i>–Δ effects. The seismic response is determined by nonlinear static and incremental dynamic analyses and the mean annual frequency of exceedance of the Significant Damage (SD) and Near Collapse (NC) limit states is computed. In a second stage, each structure is re-designed and analyzed considering <i>P</i>–Δ effects. <i>P</i>–Δ effects are counteracted in design according to provisions of European, American and Canadian seismic codes or according to other formulations proposed in literature, such as that proposed by Bernal and that proposed by the authors. The accuracy of the design provisions accounting for <i>P</i>–Δ effects is determined by comparing the response of the structures designed in the first and in the second stages. |
| first_indexed | 2024-03-11T08:25:04Z |
| format | Article |
| id | doaj.art-5277fac9b4b54eeb9ddc105de5936fab |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-11T08:25:04Z |
| publishDate | 2023-02-01 |
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| series | Metals |
| spelling | doaj.art-5277fac9b4b54eeb9ddc105de5936fab2023-11-16T22:07:42ZengMDPI AGMetals2075-47012023-02-0113232110.3390/met13020321Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting FramesFrancesca Barbagallo0Melina Bosco1Andrea Floridia2Edoardo M. Marino3Pier Paolo Rossi4Department of Civil Engineering and Architecture, University of Catania, 95100 Catania, ItalyDepartment of Civil Engineering and Architecture, University of Catania, 95100 Catania, ItalyDepartment of Civil Engineering and Architecture, University of Catania, 95100 Catania, ItalyDepartment of Civil Engineering and Architecture, University of Catania, 95100 Catania, ItalyDepartment of Civil Engineering and Architecture, University of Catania, 95100 Catania, ItalyThe seismic response of structures is always influenced by second order (<i>P</i>–Δ) effects. The importance of these effects becomes significant when the structure experiences large plastic deformations. Seismic codes indicate that <i>P</i>–Δ effects may be counteracted by means of an increase of the lateral strength required by a first order analysis, but the expressions of the Strength Amplification Factor (SAF) given in codes are often criticized by researchers. This paper proposes and validates a formulation of the SAF for Moment Resisting Frames (MRFs), which is a generalization of that derived in the past by some of the authors based on the response of SDOF systems. To this end, in a first stage of the research a set of steel MRFs is designed and analyzed neglecting <i>P</i>–Δ effects. The seismic response is determined by nonlinear static and incremental dynamic analyses and the mean annual frequency of exceedance of the Significant Damage (SD) and Near Collapse (NC) limit states is computed. In a second stage, each structure is re-designed and analyzed considering <i>P</i>–Δ effects. <i>P</i>–Δ effects are counteracted in design according to provisions of European, American and Canadian seismic codes or according to other formulations proposed in literature, such as that proposed by Bernal and that proposed by the authors. The accuracy of the design provisions accounting for <i>P</i>–Δ effects is determined by comparing the response of the structures designed in the first and in the second stages.https://www.mdpi.com/2075-4701/13/2/321second order effectsseismic codesnonlinear analyses |
| spellingShingle | Francesca Barbagallo Melina Bosco Andrea Floridia Edoardo M. Marino Pier Paolo Rossi Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames Metals second order effects seismic codes nonlinear analyses |
| title | Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames |
| title_full | Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames |
| title_fullStr | Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames |
| title_full_unstemmed | Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames |
| title_short | Effectiveness of Design Procedures in Counteracting Second Order Effects in Steel Moment Resisting Frames |
| title_sort | effectiveness of design procedures in counteracting second order effects in steel moment resisting frames |
| topic | second order effects seismic codes nonlinear analyses |
| url | https://www.mdpi.com/2075-4701/13/2/321 |
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