PSI - Issue 52

Sairam Neridu et al. / Procedia Structural Integrity 52 (2024) 267–279 Sairam Neridu/ Structural Integrity Procedia 00 (2019) 000 – 000

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1. Introduction Highway bridges play a crucial role in facilitating transportation, promoting social interactions, emergency response, and public safety while driving economic growth. They are designed to be resilient and withstand extreme weather conditions, heavy loads, and other external factors that may impact their stability presented by Hasan, M.A. et al. (2015) Despite this, bridge failures can occur for various reasons, such as material, connection, and structural failures. Regular inspections, maintenance, and effective design and construction practices are necessary to prevent bridge failures Terejanu et al. (2016), Moan et al. (2016), Douglas et al. (2016), and Murphy et al. (2016) presented a review of the current practice and future challenges of bridge maintenance and management. In India, assessing and retrofitting distressed bridges is crucial due to the country's ageing infrastructure network. The initial step in the process is to identify potential vulnerabilities within the bridge system, followed by employing retrofitting techniques to address any structural deficiencies. The retrofitting process for distressed bridges differs significantly from designing a new bridge because it requires the consideration of pre-existing structures and potential limitations imposed by those structures. Therefore, a comprehensive understanding of the bridge system and its current condition is vital in retrofitting distressed bridges to ensure their safety and extend their lifespan discussed by Thiruvengadam et al (2019) and the Ministry of Road Transport and Highways (2019). This paper aims to investigate the challenges of assessing and retrofitting distressed bridges in India and emphasizes the importance of regular monitoring, inspection, and maintenance to ensure the safe and efficient movement of people and goods, promoting public safety and economic growth. It also presents a case study of the retrofitting process of a twin culvert bridge in India, highlighting the steps involved, such as identifying the existing bridge condition, selecting a suitable retrofitting technique, considering construction work and traffic disruption, and keeping the overall cost proportional to the value of the bridge. 2. Literature review In recent years, there has been a significant research focus on addressing the issue of bridge failures. Torkelson et al. (2021) investigated the causes of bridge failures in the United States and concluded that improved maintenance and inspection programs are necessary. Ali et al. (2020) proposed a new method for assessing the vulnerability of bridges to natural disasters, which incorporates both structural and environmental factors. Multi-disciplinary approaches, combining engineering, materials science, and risk management, are critical to effectively addressing the problem of bridge failures, according to Kumar et al. (2021) and Mousavi et al. (2019). Comprehensive solutions are needed, involving design, construction, maintenance, and inspection. Proper maintenance and inspection practices can help prevent failures and extend the service life of bridges. Advanced technologies and materials, such as fibre-reinforced polymers and self-healing concrete, can enhance the durability and resilience of bridges. Non-destructive testing techniques, as presented by Li et al. (2020), can help identify potential problems before they become serious. As infrastructure ages and traffic loads increase, restrengthening techniques for reinforced concrete (RCC) bridges have been evolving. S. Ali, Duan et al. (2020), Y. Hu and X. Zhang (2021), Z. Liu et al. (2019), and M. R. Mansouri et al. (2018) have presented new trends in restrengthening techniques. External Post-Tensioning (EPT) involves adding external tendons to the bridge to increase its load-carrying capacity. Steel Plate Bonding (SPB) involves bonding steel plates to the surface of the bridge to increase its flexural and shear strength. Near-Surface Mounted (NSM) Reinforcement involves embedding steel reinforcement bars in grooves cut into the surface of the bridge, and then grouting them in place, thereby increasing the flexural and shear strength of the bridge. High-Performance Fiber Reinforced Concrete (HPFRC) is a new type of concrete that contains fibres, enhancing the strength and durability of the concrete and making it an ideal material for restrengthening bridge components. Carbon Fiber Reinforced Polymer (CFRP) Wrapping involves wrapping the bridge component with a carbon fibre-reinforced polymer sheet and bonding it to the surface using epoxy resins, providing additional strength to the bridge. Continued research and innovation in this field are essential to ensure the safety and durability of our transportation infrastructure. A study by Rajeev Kumar Garg et al. (2022) compiled a nationwide database of bridge failures in India from 1977 2017, which revealed that 2010 bridges in service and 123 under construction had reported damage or collapse during