Cross-Section Enlargement Reinforcement and Mechanical Calculation Analysis of In-Service Masonry Slab Arch Bridges

This paper proposes a technical scheme based on carbon fiber-reinforced polymer (CFRP) bar shotcrete reinforcement to address the insufficient bearing capacity of existing stone arch bridges caused by deterioration due to aging, increased traffic loads, and environmental erosion. By analyzing the mechanical mechanism of CFRP bar reinforcement and integrating key construction techniques, a calculation method for the post-reinforcement bearing capacity of stone arch bridges is established. The effectiveness of this technique is verified through finite element simulation and load testing. The results indicate that the maximum strain of the reinforced bridge is reduced by 0.3 MPa, the maximum deflection is decreased by 0.48 mm, and the bearing capacity is significantly enhanced, meeting the requirements of Highway-Ⅱ load standards. Additionally, this technology offers advantages such as convenient construction, excellent durability, and minimal disruption to traffic, providing a cost-effective solution for the reinforcement and renovation of existing stone arch bridges. Received: 28.05.2025 Received in revised form: 12.06.2026 Accepted: 02.07.2026