A Variable-Weight Model for Evaluating the Technical Condition of Urban Viaducts

Abstract

Urban viaducts play a crucial role in transportation infrastructure and are closely linked to urban resilience. Accurate evaluation of their structural technical condition forms the basis for the scientific maintenance of urban viaducts. Currently, there is a lack of technical condition evaluation specifications for viaducts in China, and the existing bridge specifications that are similar do not fully align with the facility composition characteristics and maintenance management needs of viaducts. Therefore, this paper presents a technical condition assessment model for viaducts, based on existing bridge specifications. Considering the frequent damage to ancillary facilities of viaducts, the utilization of maintenance resources, and the impact on traffic operations, the model proposed in this paper adopts the Analytic Hierarchy Process (AHP) to introduce a new indicator layer for ancillary facilities. Subsequently, the weight values and deduction values of each layer of the model, as well as the findings of damage recorded in the new components, were determined using the Group Decision-Making (GDM) method and the Delphi method. This process forms a constant-weight evaluation model for assessing the technical condition of viaducts. Finally, to account for the impacts of significant damage to low-weight components on the structural condition, the variable-weight method was adopted to establish a comprehensive evaluation model with variable weights, which was then validated using practical viaduct examples. The results indicate that the variable-weight model provides a more accurate representation of the technical condition of viaducts, especially when components are severely damaged. Furthermore, this study examines the suitable conditions for implementing the constant-weight evaluation model and the variable-weight evaluation model, demonstrating that the variable-weight model is recommended when there is a significant disparity in the scores among the viaduct components, whereas the constant-weight model is applicable in other scenarios.