PSI - Issue 70

Abhishek Badalia et al. / Procedia Structural Integrity 70 (2025) 121–128

128

Conclusions

• Unbraced frames have significantly lower lateral stiffness and would be highly vulnerable to lateral forces. • Use of braces in existing RC OMRF enhances seismic performance when provided at end bays of the frame along its periphery in both principal plan directions for a building with a square plan geometry. • X-bracing shows the highest reduction in base shear, indicating the superior performance in resisting lateral forces. Other bracing types, such as X-intersecting, Chevron, V, and Diagonal braces, show a small but stable reduction in base shear when compared to an unbraced frame because of increased lateral resistance as a part of the elevated stiffness and controlling inter-storey drift in the structure. • Both X and Chevron bracing configurations resulted in higher natural frequencies and lower mode shapes compared to other braced frames and the unbraced frames. • Based on findings X-braced configuration at the end bays of the peripheral frame can be the best possible recommendation for retrofitting a mid-rise building with a square or similar plan geometry. • The structural stiffness of the frame should be controlled to prevent the attraction of higher inertia forces that may jeopardize its integrity. • Future studies should focus on optimizing bracing patterns for different building heights and conducting full scale experimental validations to complement numerical simulations. References Ahiwale, D.D., Kontoni, D.P.N., Darekar, P.L., 2023. Seismic performance assessment of reinforced concrete frames with different bracing systems. Innovative Infrastructure Solutions 8. Babu, A., KumarPatnaikuni, C., Kumar, Bs., 2017. Effect of Steel Bracings on RC Framed Structure, International Journal of Mechanics and Solids. Bhattacharya, S., Nayak, S., Dutta, S.C., 2014. A critical review of retrofitting methods for unreinforced masonry structures. International Journal of Disaster Risk Reduction. Boru, e., Aydin, e ., 2022. The Effect of Different Steel Brace Types on Reinforced Concrete Frame System Retrofit. Türk Doğa ve Fen Dergisi 11, 118 – 124. Castro, J.M., Araújo, M., D’Aniello, M., Landolfo, R., 2018. Strengthening of RC Buildings with Steel Elements. pp. 139 – 162. Desai, A., 2010. From IP-117.240.195.179 on dated 24. Faella, C., Lima, C., Martinelli, E., Realfonzo, R., 2014. Steel bracing configurations for seismic retrofitting of a reinforced concrete frame. Proceedings of the Institution of Civil Engineers: Structures and Buildings 167, 54 – 65. Jain, S.K., 1998. Indian Earthquakes: An Overview, The Indian Concrete Journal. Joseph, R., Mwafy, A., Alam, M.S., 2022. Seismic performance upgrade of substandard RC buildings with different structural systems using advanced retrofit techniques. Journal of Building Engineering 59. Kulkarni, J.G., Kore, P.N., Tanawade, S.B., 2013 Seismic Response of Reinforced Concrete Braced Frames. International Journal of Engineering Research and Applications (IJERA) www.ijera.com 3, 1047 – 1053. Marc Badoux, B., Jirsa, J.O., 1991. Steel bracing of RC frames for seismic retrofitting. Nateghi-A, F., 1995. Seismic strengthening of eight-storey RC apartment building using steel braces, Engineering Structures. Navya, G., Agarwal, P., 2016. Seismic Retrofitting of Structures by Steel Bracings, in: Procedia Engineering. Elsevier Ltd, pp. 1364 – 1372. Pohoryles, D.A., Bournas, D.A., Da Porto, F., Caprino, A., Santarsiero, G., Triantafillou, T., 2022. Integrated seismic and energy retrofitting of existing buildings: A state-of-the-art review. Journal of Building Engineering 61, 105274. Poudel, A., Suwal, R., 2020. Seismic Performance Analysis of RC Frame Building Using Different Types of Steel Bracing, International Advance Journal of Engineering Research (IAJER). Ranganadhan, A., Paul, A., 2015 seismic retrofitting of an existing structure, IJRET: International Journal of Research in Engineering and Technology. Shen, J., Seker, O., Akbas, B., Seker, P., Momenzadeh, S., Faytarouni, M., 2017. Seismic performance of concentrically braced frames with and without brace buckling. Eng Struct 141, 461 – 481. Tahamouli Roudsari, M., Entezari, A., Hadidi, M.H., Gandomian, O., 2017. Experimental Assessment of Retrofitted RC Frames with Different Steel Braces. Structures 11, 206 – 217.