Project code: PN-III-P1-1.1-PD-2016-1655, contract number PD 139 / 2018
Funding source
The project is supported by a grant of Ministery of Research and Innovation, CNCS - UEFISCDI, project number PN-III-P1-1.1-PD-2016-1655, within PNCDI III.
Project objective
The project aims at extending the validation of re-centering capability and link replacement feasibility of eccentrically braced frames with bolted links on extended end-plate typologies and also investigate more detailed the global and local influence of three-dimensional reinforced concrete slab panels, as well as reinforced concrete slab repair.
Project abstract
There are concerns about life loss and economic damage in the event of a major earthquake worldwide. Therefore, structural engineers must concentrate in increasing seismic safety without attracting excessive costs. Eccentrically braced frames (EBFs) provide a convenient balance between stiffness and ductility. To reduce repair costs and downtime of a structure hit by an earthquake, the concepts of removable dissipative members (bolted links which are intended to provide the energy dissipation capacity and to be easily replaceable) and re-centering capability (provided by the more flexible moment resisting frames) can be implemented in a dual structure, obtained by combining steel eccentrically braced frames with removable bolted links with moment resisting frames (MRFs). Seismic performance, re-centering capability and link replacement feasibility of such systems with removable flush end-plate bolted links were studied before. In order to generalize the approach, the present research aims at extending and validating these investigations on other link typologies, like extended end-plate bolted links. One of the critiques to the removable link solution is related to interaction between the removable link and the concrete slab, which can affect the link shear capacity. Large link deformations can damage the concrete slab, which violates the principle that plastic deformations are constrained to removable links only. Past research revealed that the increase in lateral stiffness and unexpected ability to self-center in EBFs is due to the out-of-plane stiffness of the floor slabs. Several numerical investigations, as well as experimental programs used the approach of plane frame with narrow concrete strip to study this behavior, but this assumption would not lead to an accurate out of plane stiffness of the slab. This will be revised and improved within the proposed research by investigation of effects of 3D slab panel on EBF. Slab repair solutions will be applied.
Period of the project
10.10.2018 – 13.11.2020
Expected results
The estimated results consist in obtaining material behavior curves, testing campaign experimental results which describe the studied behavior, both local and global, calibrated numerical models of links and values of behavior factors for structures.
Obtained results
Activity reports
- Technical and scientific report stage 1 / 2018: Design of prototype structures; Design and manufacture of experimental program – first part
- Technical and scientific report stage 2 / 2019: Design and manufacture of experimental program – second part; Experimental program – first part; Numerical investigations – first part
- Technical and scientific report stage 3 / 2020: Experimental program – second part; Numerical investigations - second part
- Final technical and scientific report
Scientific articles
Influence of link length on re-centering capability of dual eccentrically braced frames
Experimental investigation of length influence on removable links
Other results
- Deliverable D1: Design of prototype structures and link removal numerical procedure description
- Deliverable D2: Technical project of experimental setup and specimens
- Deliverable D3_a: Description of experimental tests: materials behavior curves, data describing links behavior during tests
- Deliverable D4_a: Calibrated numerical models for isolated links
- Deliverable D3_b: Description of experimental tests: data describing frames behavior during tests + addition to D3_a: data describing links behavior during tests
- Deliverable D4_b: Performance assessment of the system + addition to D4_a: Calibrated numerical models for isolated links
Contact
Adriana Chesoan
Universitatea Politehnica Timișoara
Facultatea de Construcții
Departamentul de Construcții Metalice și Mecanica Construcțiilor
str. Ioan Curea nr.1
300224 Timișoara
Romania
tel: +40 256 403925
email: adriana.chesoan@upt.ro