2022 Fiscal Year Research-status Report
Multi-hazard resilient structural system adopting strong structural spines and damped-pin joints
| Project/Area Number |
22K14362
|
|---|
| Research Institution | Hiroshima University |
|---|
Principal Investigator |
陳 星辰 広島大学, 先進理工系科学研究科(工), 助教 (00816564)
|
|---|
| Project Period (FY) |
2022-04-01 – 2024-03-31
|
| Keywords | damped-pin joint / cyclic loading test / numerical analysis / theoretical evaluation |
|---|
| Outline of Annual Research Achievements |
This research aims to develop a multi-hazard resilient structural system adopting strong structural spines and damped-pin joints. In the first year, two types of damped-pin joints were proposed to enhance resilience of typical strong-spine structures as well as regular moment frame structures. The structural characteristics of the damped-pin joints were clarified through cyclic loading tests and finite element analysis. Those damped-pin joints can be applied at the collector ends in the strong-spine structures and beam-to-column connections in moment frame structures. One of the proposed joints uses lever-arm members to place dampers in the vertical structural members rather than the horizontal members, which enhances the flexibility of damper arrangements. The other proposal introduces double-stage yield dampers to realize multi-stage vibration control of the structure. Stiffness and strength evaluation methods for the two types of damped joints were developed based on theoretical analysis. Feasibility of the proposed joints and the evaluation methods were verified by cyclic loading tests and computer simulation. Efficiency of the double-stage yield dampers were also verified by seismic response analysis of building models under various ground motion inputs. Additionally, two solutions to reduce column base damage in the strong-spine structures have been discussed through numerical analyses, which are increasing the first-story height and raising the pin base location of the structural spines.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
The research progressing smoothly as the original plan in general. Two types of damped-pin joints have been proposed. The feasibility and efficiency of them have been verified by both cyclic loading tests and numerical simulation. The original idea in the application form was to apply the damped-pin joints at the collector ends in the strong-spine system. For achieving a wide application of such joints, regular beam-to-column connections were included as the research subjective. Furthermore, solutions to reduce column base damage in the strong-spine structures have been discussed through time-history response analyses of member-by-member structure models. The approach of increasing the first-story height and raising the pin base location of the structural spines have been investigated through parametric study. Simultaneously, general stiffness/strength index integrating these solutions are under construction. Literature reviews on external forces representing different hazards have been carried out and analysis models have been created for the extensive numerical analysis in the next step.
|
| Strategy for Future Research Activity |
Investigation on the solutions to reduce column base damage will continue. The stiffness/strength index for evaluating these solutions need to be further discussed. The relationship between the stiffness ratio index and the column base damage concentration will be elucidated by numerical analysis. The representative models will be verified by shaking table tests on reduced-scale multi-story spine frame specimens. The performance of the proposed strong-spine system will be clarified by numerical analysis considering different natural-hazard effects, which include earthquake, wind, flood, and tsunami. A new evaluation method for determine the stiffness demand of the structural spine will be proposed. The evaluation and design methods of the proposed system will be established by using the simplified multi-degree-of-freedom models and verified by numerical analysis and tests. Clear suggestions will be obtained for the essential parameters including the damped-pin joints properties, first-story stiffness ratio of the moment frame and the spine, and stiffness demands of the spine.
|
