Abstract
Variation of temperature is a primary environmental factor that affects the behavior of structures. Therefore, understanding the mechanisms of normal temperature-induced variations of structural behavior would help in distinguishing them from anomalies. In this study, we used the structural health monitoring data of the Shanghai Yangtze River Bridge, a steel girder cable-stayed bridge, to investigate the mechanisms of thermally induced vertical deflection (<TEX>$D_T$</TEX>) at mid-span of such bridges. The <TEX>$D_T$</TEX> results from a multisource combination of thermal expansion effects of the cable temperature (<TEX>$T_{Cab}$</TEX>), girder temperature (<TEX>$T_{Gir}$</TEX>), girder differential temperature (<TEX>$T_{Dif}$</TEX>), and tower temperature (<TEX>$T_{Tow}$</TEX>). It could be approximated by multiple linear superpositions under operational conditions. The sensitivities of <TEX>$D_T$</TEX> of the Shanghai Yangtze River Bridge to the above temperatures were in the following order: <TEX>$T_{Cab}$</TEX> > <TEX>$T_{Gir}$</TEX> > <TEX>$T_{Tow}$</TEX> > <TEX>$T_{Dif}$</TEX>. However, the direction of the effect of <TEX>$T_{Cab}$</TEX> was observed to be opposite to that of the other three temperatures, and the magnitudes of the effects of <TEX>$T_{Cab}$</TEX> and <TEX>$T_{Gir}$</TEX> were found to be almost one order greater than those of <TEX>$T_{Dif}$</TEX> and <TEX>$T_{Tow}$</TEX>. The mechanisms of the thermally induced vertical deflection variation at mid-span of a cable-stayed bridge as well as the analytical methodology adopted in this study could be applicable for other long-span cable-stayed bridges.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call