Bridge fires present unique challenges due to their potential for catastrophic structural failures, leading to extensive traffic disruptions, economic losses, and, in some cases, loss of life. In the aftermath of a fire incident, assessing the structural integrity and future viability of concrete bridges has become a paramount concern for civil engineers and safety inspectors. The critical decision to rehabilitate or demolish a fire-damaged structure hinges on accurately assessing the extent of damage incurred. Enhancing the fire resilience of concrete structures is a critical endeavor within civil engineering, necessitating accurate evaluation methods to analyze conditions after fire exposure. Focusing on concrete bridges, this study aimed to establish a comprehensive review of research on the effects of fire, providing engineers with the necessary means to develop guidelines for post-fire assessment to enhance safety and operational readiness. It proposes an in-depth examination of various methods as strategic decision-making tools. The assessment involves estimating the temperature, the extent of damage to concrete, and the reduction in the strength of both concrete and reinforcement. To achieve this, a detailed review of the existing literature on the impact of fire on concrete and its steel reinforcements is conducted. Current post-fire assessment tools have also been evaluated to improve the efficiency of the evaluation process. This study establishes a systematic post-fire assessment review framework that incorporates assessment information domains (including non-destructive testing, destructive testing, advanced computational modeling, and digital-twin technology) to provide a practical solution for accurately determining the safety and operational readiness of fire-damaged concrete bridges.

Large-span post-tensioned (PT) beams play a crucial role in maximizing the benefits of post-tensioning techniques. Bonded and unbonded systems are prevalent, with the latter being more widespread in the United States. While bonded systems are advantageous for creating long spans when multiple tendons are grouped in ducts, limited literature exists on their demolition. In a case study, this paper addresses the unique challenge of demolishing large-span bonded post-tensioned beams due to a building's functional change. Emphasizing insights for engineers, it explores the use of cutting and dismantling methods, considering the presence of prestressed cables. The demolition process is distinctive due to the presence of numerous pre-stressed cables along the beams, necessitating a specialized and cautious cutting approach. This is accomplished through the use of a drilling technique that selectively distresses the tendons, ensuring they are not all affected simultaneously. An intriguing observation discussed in this paper pertains to the occurrence of horizontal cracks accompanied by loud sounds following the drilling process, offering insights from the design perspective of PT systems. The paper details an innovative method for safely demolishing large-span bonded PT beams, using ground-penetrating radar and computer models to navigate structural complexities and ensure nearby structures' safety.

Large-span, post-tensioned (PT) beams play a crucial role in maximizing the benefits of post-tensioning techniques. Bonded and unbonded systems are prevalent, with the latter being more widespread in the United States. While bonded systems are advantageous for creating long spans when multiple tendons are grouped in ducts, limited studies in the literature exist on their demolition. With a case study, this paper addresses the unique challenge of demolishing large-span-bonded, post-tensioned beams that occurs due to a building’s functional change. Emphasizing insights for engineers, it explores the use of cutting and dismantling methods, thereby considering the presence of prestressed cables. The demolition process is distinctive due to the presence of numerous prestressed cables along the beams, necessitating a specialized and cautious cutting approach. This is accomplished through the use of a drilling technique that selectively distresses the tendons, ensuring they are not all affected simultaneously. An intriguing observation discussed in this paper pertains to the occurrence of horizontal cracks accompanied by loud sounds following the drilling process, thereby offering insights from the design perspective of PT systems. This paper details an innovative method for safely demolishing large-span, bonded PT beams using ground-penetrating radar and computer models to navigate structural complexities and ensure nearby structures’ safety.