Work

Damage evaluation of assembled small box-girder bridges under stochastic traffic via nominal neutral axis

Year: 2026

Type: article

Abstract: With the continuous growth of traffic volume, many assembled small box-girder bridges have exceeded their design capacities, resulting in structural cracks and deformations. Accurately evaluating damage degrees and residual bearing capacities under operational conditions remains a significant challenge. This paper proposes a novel structural evaluation method based on the nominal neutral axis (NNA). Unlike traditional indicators, the NNA represents the intrinsic nature of the cross-section and is not affected by load excitation. We objectively determine the NNA using a statistical method applied to strain data collected under stochastic traffic flow. Based on the NNA, a unique nonlinear evaluation index δ is established to quantify the deviation from the plane section assumption. The reliability of the δ index was strictly verified through finite element modeling and a targeted short-term strain monitoring test on a real bridge under both controlled static loads and actual stochastic traffic. The results demonstrate that the NNA can be accurately identified under stochastic traffic conditions. The proposed δ index effectively characterizes the structural state, quantifies damage extent, and assesses the remaining load-carrying capacity. Specifically, the δ value intervals allow for the clear distinction between the structure’s elastic stage, cracked working stage, and plastic stage. This method provides a practical, reliable, and high-efficiency solution for the rapid assessment of bridge conditions without requiring traffic closure. It offers a valuable tool for transportation departments to prioritize maintenance and ensure the operational safety of aging bridge infrastructure.

Source: Measurement Science and Technology

DOI: 10.1088/1361-6501/ae4054

Authors: Shizhan Xu, Niannian Zheng, Zhigang Zhao, Weili He

Institution: Zhengzhou University

Language: English

Topic: Structural Health Monitoring Techniques

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Industry, innovation and infrastructure, Sustainable cities and communities

Open Access status: hybrid

Estimated APC paid: $3,325