STUDYON TEMPERATURE SENSITIVITY COEFFICIENTS OF MID-SPAN VERTICAL DISPLACEMENT OF CABLE-STAYED BRIDGES

The variation in the mid-span vertical displacement of bridges with ambient temperature changes is a great concern for structural health monitoring. The previous study has shown that the cable temperature and the average girder temperature dominate the girder’s mid-span vertical displacement of a cable-stayed bridge. By using plane geometric analysis and a series expansion, this paper presents a simplified calculation formulas of the temperature sensitivity coefficients of the mid-span vertical displacement of symmetric twin-tower cable-stayed bridges with respect to the cable temperature and the average girder temperature. The formulas reflect the root causes of thermal deformation and reveal the quantitative relationships between the temperature sensitivity coefficients and the material property (linear expansion coefficients) and structural geometries (main span length L₀, side-to-center span ratio γ₀, and tower-height-to-span ratio ζ). This study provides a novel solution to the temperature-induced deformation of cable-stayed bridges.