Thermal performance analysis of a long-span suspension bridge with long-term monitoring data

Thermal performance analysis such as calculating thermal stress from monitoring data is important for structural safety evaluation. These temperature characteristics of long-span bridges are more complicated due to their temperature distribution, structural configuration and boundary conditions. In this study, the method of structural thermal performance analysis is proposed by processing and analyzing the long-term monitoring data and it is applied to study the thermal and mechanical behavior of a long-span suspension bridge under daily operating conditions. First, statistical analysis of strain data and temperature data is performed on the main girder. Second, thermal analysis and temperature-induced stress calculation are proposed, in which the different kinds of thermal loads including uniform temperature, linear/nonlinear temperature gradient and partial constraints in axial/rotation directions are considered. Other parameters such as restrained stiffness, deformation, etc., are derived. Third, the proposed method is verified and used in the temperature-induced stress calculation on the studied bridge.