PSI - Issue 71

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ScienceDirect

Procedia Structural Integrity 71 (2025) 233–240

Retrofitting involves providing some modifications and alterations to increase the resistance to seismic activity of the existing structures. It is generally more cost-effective than demolishing and rebuilding because it utilizes the existing structure as a base. FBD and PBD are design philosophies that guide how retrofitting should be implemented to enhance a structure’s seismic performance. The actual retrofitting methods applied (such as jacketing, bracing, or base isolation) are chosen based on these design approaches to achieve the desired level of safety and performance Hosur, V. (2012). Hence seismic retrofitting and building structures strengthening are the most significant factors in earthquake prone areas. There are two methods of seismic, retrofitting and strengthening i.e. using the addition of new structural 1.1. Retrofitting of Reinforced Concrete Structure Following an earthquake, extensive damages are often found in varying degrees, resulting in irreparable loss of life and widespread destruction Baikerikar and Kanagali (2014). Existing reinforced concrete (RC) framed buildings are designed without seismic and ductile criteria which causes hazards during earthquakes. An upgraded seismic performance can be realized with two different approaches to overcome the present deficiencies. Designing RC frame structures for seismic and ductile performance can be approached in two main ways: Force-Based Design (FBD) and Performance-Based Design (PBD) Bush et al.(1991). FBD follows code-based guidelines to ensure buildings can resist calculated forces, but it may not fully address how a building performs beyond its elastic limit. PBD uses detailed analyses to make sure buildings meet specific performance goals under various seismic conditions, resulting in better overall resilience and safety. Reinforced shear walls and steel bracing systems are FBD, whereas local strengthening, as per the requirement of some structural building elements, using concrete, steel reinforcement, and fiber reinforced polymer are PBD. 1. Introduction Keywords: Retrofitting; Seismic Performance; Steel Bracings Abstract Steel-braced frames play a crucial role in resisting earthquake loads in multi-storied buildings. To mitigate seismic damage, many existing reinforced concrete (RC) frame structures are retrofitted to enhance their load resistance capabilities. The use of steel bracing systems in structures for strengthening and retrofitting during earthquakes provides a structurally efficient means of resisting seismic loads and improving overall building stability. The bracing system of steel is easy to construct and economical. Its space consumption is less and it can be designed for the desired stiffness and strength. This paper presents research work on the performance of RC frame structure buildings in seismic loading conditions rehabilitated by using concentric steel bracing. These bracings are provided in column peripherals. In this study, analysis for seismic zone IV of a four-storey building is done by referring to IS1893:2016 and using the software STAAD Pro V8i. The research focuses on evaluating the efficiency of various bracing systems implemented in the restoration of four-storey structures. The effect of the steel bracing distribution on the height of the building frame for the seismic resistivity performance is studied. This is to ensure the seismic performance, and the effects created in the building are studied. This effect of building is evaluated by using global and local retrofit methods. From this study, it is found that the system of providing bracings that contributes to the structural stiffness and decreases the maximum inner storey drifts is an X-type of bracing system. This study is useful for analyzing the Eight, Twelve, and Sixteen storey buildings. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of SICE 2024 organizers Nisha Thakur a , Minal Kitey b , Harshad Phadke a , Vikas Thakur a a Department of Civil Engineering, Bajaj Institute of Technology, Pipri, Wardha, 442001, Maharashtra, India b Department of Civil Engineering, Bharat College of Engineering, Kanhor, Badlapur (W), 421503, Maharashtra, India 5 th International Structural Integrity Conference & Exhibition (SICE 2024) Seismic Behavior of Steel-braced RC Frames in Seismic Zone IV

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of SICE 2024 organizers 10.1016/j.prostr.2025.08.032