•
Lateral strength and energy dissipation potential of the retrofitted frame is significantly higher than the original RC specimen. However, a premature failure of the connection between the combined metallic yielding damper and beam can be expected if the damaged beam was not strengthened at the damper location.
•
The retrofitted frame exhibited a higher lateral load resistance compared to the original SFRC frame. The energy dissipation potential of the damaged frame can be improved by 2.5 times if the CMD is used as passive energy dissipation device in the damaged frame.
•
This study showed that the proposed strengthening technique can be adopted to improve the seismic performance of a damaged RC structure located in low-to-medium intensity seismic regions in practice. Table 2: Computation of equivalent damping potential of the test frames Drift level (%)
Energy dissipated, Eloop (kNmm)
Effective stiffness, Keq (kN/mm)
8.96
16.12
2.89
3.59
6.17
2.
Alehashem, S. M. S., Keyhani, A., and Pourmohammad, H. (2008). “Behavior and Performance of Structures Equipped With ADAS & TADAS Dampers (a Comparison with Conventional Structures).” The 14th World Conference Earthquake Engineering, Beijing, China.
3.
Campione, G. (2013). “RC Columns Strengthened with Steel Angles and Battens : Experimental Results and Design Procedure.” Practice Periodical on Structural Design and Construction, ASCE, 18 (February), 1–11.
4.
FEMA-356 (2000). Prestandard and Commentary for the Seismic Rehabilitation of Buildings. Federal Emergency Management Agency, Washington, DC.
5.
Hannant, D. J. (1978). Fibre Cements and Fibre Concretes. Wiley-Interscience, New York, 219.
6.
IS-10262. (2009). “Concrete Mix ProportioningGuidelines.” Bureau of Indian Standards, New Delhi.
7.
IS-456. (2000). “Plain and Reinforced Concrete – Code of Practice.” Bureau of Indian Standards, New Delhi.
8.
Jain, S. K., and Uma, S. R. (2006). “Seismic Design of Beam Column Joints in RC Momentresisting Frames- Review of Codes.” Structural Engineering and Mechanics, 23(5), 579–597.
9.
Kaplan, H., and Salih, Y. (2011). “Seismic Strengthening of Reinforced Concrete Buildings.” Earthquake-Resistant Structures - Design, Assessment and Rehabilitation, A. Moustafa, ed., Turkey, 407–428.
8.46
0.25
21.57
41.90
2.84
3.74
9.21
13.55
43.50
97.47
2.94
4.34
9.18
13.81
0.50
89.07
221.24
3.01
4.25
8.91
15.54
0.75
195.76
442.40
2.66
3.81
9.69
15.37
1.00
354.30
1086.73
2.41
3.77
10.82
21.86
1.40
671.50
2196.37
2.13
3.98
11.78
20.81
1.75
1030.23
3854.33
1.93
4.10
12.16
23.21
2.20
1562.57
6345.33
1.77
3.81
13.13
25.82
2.75
2369.67
9346.00
1.58
3.20
14.18
30.78
3.50
3661.00
11920.00
1.36
2.06
15.68
37.14
4.50
5616.00
14294.33
1.11
1.40
17.80
38.87
17585.33
ACI, Committee 374.1-05 (2006). “Acceptance Criteria for Moment Frames based on Structural Testing and Commentary- An ACI Standard.” American Concrete Institute, Farmington Hills, Michigan.
ßeq (%)
0.35
6.00
1.
Equivalent damping,
Original Retrofitted Original Retrofitted Original Retrofitted 0.20
References
0.99
35.87
Acknowledgments The funding received from Department of Science and Technology (DST) and Government of India (GOI) in carrying out this research is greatly acknowledged. Authors are thankful to the staff members of Heavy Structures Laboratory, Department of Civil Engineering, IIT Delhi for their support in conducting the experimental investigation. The Bridge and Structural Engineer
10. Moehle, J. P. (2000). “State of Research on Seismic Retrofit of Concrete Building Structures in the US.” US-Japan Symposium and Workshop on Seismic Retrofit of Concrete Structures— State of Research and Practice. Volume 45 Number 1 March 2015
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