Retrofit Strategies against Progressive Collapse of Steel Gravity Frames
Two retrofit strategies, aiming at increasing the collapse resistance of simple connections by adding seat angles and steel plates with long-slotted holes, are proposed in order to address the vulnerability of steel gravity frames under column loss scenarios. A high-fidelity, detailed, finite elemen...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-07-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/10/13/4600 |
| _version_ | 1797563366080774144 |
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| author | Lei Zhang Honghao Li Wei Wang |
| author_facet | Lei Zhang Honghao Li Wei Wang |
| author_sort | Lei Zhang |
| collection | DOAJ |
| description | Two retrofit strategies, aiming at increasing the collapse resistance of simple connections by adding seat angles and steel plates with long-slotted holes, are proposed in order to address the vulnerability of steel gravity frames under column loss scenarios. A high-fidelity, detailed, finite element model for a planar composite frame is developed and calibrated against experimental data and is used to conduct numerical analysis to explore the effectiveness of the proposed retrofit strategies. The simulation results show that the planar composite frame with enhanced connections exhibits significantly higher collapse resistance and better ductility under column loss scenarios compared with the one with conventional connections. Meanwhile, it is also revealed that the proposed retrofit strategies have an insignificant impact on the behavior of the structural system under earthquakes. These two retrofit strategies are then implemented to retrofit the gravity system of a 10-story, seismically designed steel frame structure, which has been shown to be vulnerable to progressive collapse after an interior gravity column is forcibly removed or impacted by a heavy vehicle with high speed. Numerical simulations were performed using a 3-D micro-based model and the simulation results illustrate that progressive collapse of the structure with enhanced gravity systems is prevented under both scenarios. Therefore, the proposed retrofit strategies are effective in preventing the progressive collapse of existing steel structures employing simple connections. |
| first_indexed | 2024-03-10T18:41:37Z |
| format | Article |
| id | doaj.art-7f4efe3c54374a1fa2708ce30638921a |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T18:41:37Z |
| publishDate | 2020-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-7f4efe3c54374a1fa2708ce30638921a2023-11-20T05:48:16ZengMDPI AGApplied Sciences2076-34172020-07-011013460010.3390/app10134600Retrofit Strategies against Progressive Collapse of Steel Gravity FramesLei Zhang0Honghao Li1Wei Wang2Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education, Harbin Institute of Technology, Harbin 150090, ChinaKey Lab of Structures Dynamic Behavior and Control of the Ministry of Education, Harbin Institute of Technology, Harbin 150090, ChinaKey Lab of Structures Dynamic Behavior and Control of the Ministry of Education, Harbin Institute of Technology, Harbin 150090, ChinaTwo retrofit strategies, aiming at increasing the collapse resistance of simple connections by adding seat angles and steel plates with long-slotted holes, are proposed in order to address the vulnerability of steel gravity frames under column loss scenarios. A high-fidelity, detailed, finite element model for a planar composite frame is developed and calibrated against experimental data and is used to conduct numerical analysis to explore the effectiveness of the proposed retrofit strategies. The simulation results show that the planar composite frame with enhanced connections exhibits significantly higher collapse resistance and better ductility under column loss scenarios compared with the one with conventional connections. Meanwhile, it is also revealed that the proposed retrofit strategies have an insignificant impact on the behavior of the structural system under earthquakes. These two retrofit strategies are then implemented to retrofit the gravity system of a 10-story, seismically designed steel frame structure, which has been shown to be vulnerable to progressive collapse after an interior gravity column is forcibly removed or impacted by a heavy vehicle with high speed. Numerical simulations were performed using a 3-D micro-based model and the simulation results illustrate that progressive collapse of the structure with enhanced gravity systems is prevented under both scenarios. Therefore, the proposed retrofit strategies are effective in preventing the progressive collapse of existing steel structures employing simple connections.https://www.mdpi.com/2076-3417/10/13/4600collapse resistancesimple connectionsretrofitting strategieshigh-fidelity numerical modelalternative path methodvehicle impact |
| spellingShingle | Lei Zhang Honghao Li Wei Wang Retrofit Strategies against Progressive Collapse of Steel Gravity Frames Applied Sciences collapse resistance simple connections retrofitting strategies high-fidelity numerical model alternative path method vehicle impact |
| title | Retrofit Strategies against Progressive Collapse of Steel Gravity Frames |
| title_full | Retrofit Strategies against Progressive Collapse of Steel Gravity Frames |
| title_fullStr | Retrofit Strategies against Progressive Collapse of Steel Gravity Frames |
| title_full_unstemmed | Retrofit Strategies against Progressive Collapse of Steel Gravity Frames |
| title_short | Retrofit Strategies against Progressive Collapse of Steel Gravity Frames |
| title_sort | retrofit strategies against progressive collapse of steel gravity frames |
| topic | collapse resistance simple connections retrofitting strategies high-fidelity numerical model alternative path method vehicle impact |
| url | https://www.mdpi.com/2076-3417/10/13/4600 |
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