Effect Analysis of Environmental Temperature on Dynamic Properties of Cablestayed Bridge

Abstract:

Based on oneyear monitoring data measured by the structural health monitoring system of Donghai Bridge, the effect of environmental temperature on dynamic properties of cablestayed bridge was analyzed. At first, the distribution characteristics of environmental temperature were analyzed based on the monitoring data of environmental temperature. The environmental temperature was uniformly distributed along the longitudinal direction of bridge and there was also significant temperature gradient in the cross section of box girder. The influencing mechanism of environmental temperature on dynamic properties was theoretically analyzed and was validated by the monitoring data. The results demonstrate that the theoretical analysis is consistent with the monitoring data. Finally the thermal inertial effect of the environmental temperature on dynamic properties was analyzed based on AutoRegressive model with eXogenous inputs (ARX) model. The results show that there is time lag effect of temperature on dynamic properties and the time lag effect can be equivalently evaluated by multipoint temperature data.

Key words:environmental temperature; modal parameters; cablestayed bridge; structural health monitoring