Modeling and Separation of Thermal Effects from Cable-Stayed Bridge Response

This article presents a practical multivariate linear-based model for modeling and separation of thermal effects from the cable-stayed bridge response. First, the discrete typical thermal loadings, which are the variables in the linear model, are derived from the real-time recorded temperature measurements. Then, weight coefficients (i.e., normalized response corresponding to each type of temperature action) in the model are acquired by considering the simulation results of the numerical models. Finally, the Third Nanjing Yangtze River Bridge is employed as a case study to validate the effectiveness of the proposed methodology. The reliability of the proposed multivariate linear-based model is verified on the measurements of deflection and temperature during the bridge-closure time window. The maximum error between the predicted and measured deflection is 5.6 mm, which accounts for the resolution of the connected pipe system. This study not only helps to understand the thermal field of such large-span cable-stayed bridges but also develops an effective model that separates thermal response and can benefit real-time quasi-static-based anomaly detection for large-scale bridges.