This study explores the effectiveness of external prestressed reinforcement as a method for enhancing the durability of reinforced concrete bridge structures. Over time, many bridges experience significant deterioration due to increased traffic loads, aging materials, and environmental factors, leading to reduced load-bearing capacity. External prestressed reinforcement offers a solution to extend the service life of bridges without full reconstruction. The research demonstrates that this method improves the structural rigidity of the bridge, redistributes loads more evenly, and reduces deformations, contributing to the overall longevity and reliability of the structure. Experimental data indicates that external prestressed reinforcement enhances crack resistance, increases bridge stiffness, and ensures the stability of anchor blocks. By applying this technique, it is possible to increase the load capacity of a bridge without the need for costly capital repairs. The findings suggest that this approach is an effective and economical solution for strengthening and maintaining bridges, particularly those built in previous decades, and that ongoing monitoring and quality control are crucial for optimizing its application.
Introduction. Reinforced concrete bridge structures experience significant loads during operation, leading to physical deterioration, crack formation, and a gradual decrease in load-bearing capacity. One method for extending the service life of bridges without full reconstruction is the use of external prestressed reinforcement. This method enhances the rigidity of the structure and ensures a more uniform distribution of loads, minimizing deformations.
Problem Statement. Most bridges currently in use in Ukraine were built in the 1960s–1980s according to the regulatory requirements of that period. The design loads and traffic intensity considered during their construction are significantly lower than today's actual conditions. Increased traffic intensity, the emergence of heavy vehicles, and the physical aging of materials lead to bridge overloading, causing span deformations, increased deflections, crack formation in concrete, reinforcement corrosion, reduced structural rigidity, and high capital repair costs.
Materials and methods. The material for the article is based on the experience of using external prestressed reinforcement for strengthening bridge structures in Ukraine, including the example of the overhaul of the bridge across the Rusaniv Strait in Kyiv. The following research methods were used: analysis of data from scientific sources, analysis of regulatory documents, and measurement of shear deformations on the anchor blocks of span structures.
Objective. To assess the effectiveness of external prestressed reinforcement in improving the durability of reinforced concrete bridge structures based on experimental data.
Results. The study showed that the use of external prestressed reinforcement reduces tensile stresses in concrete, enhancing crack resistance, increasing bridge stiffness, and ensuring the stability of anchoring blocks, which confirms the reliability of the tensioned element fastening. The application of external prestressed reinforcement allows for an increase in the bridge's load-bearing capacity without requiring major reconstruction.
Conclusions. The use of external prestressed reinforcement is an effective solution for restoring and extending the service life of reinforced concrete bridge structures. This method enables a uniform redistribution of loads, reduces deformations, and enhances the durability of the structure without significant financial costs. To achieve maximum efficiency, engineering monitoring of the bridge condition, modeling of the stress-strain state, and quality control during the tensioning of reinforcement bundles are necessary.
