Long-Term Temperature Monitoring and Statistical Analysis on the Flat Steel-Box Girder of Sutong Bridge

Abstract

Using the flat steel-box girder of China’s Sutong Cable-stayed Bridge as a research object, its temperature field is long-term monitored and analyzed based on bridge’s structural health monitoring system. The temperature distribution characteristics of the girder are investigated using the temperature data, and the transverse and vertical thermal differences are analyzed in detail. Using statistical methods, the corresponding probability distribution models of the temperatures and the temperature differences of the fat steel-box girder are established, and the standard values of the temperature and temperature differences within a certain return period are determined. The analysis results reveal that (1) there exist dominant vertical temperature differences between the top and bottom plates, with definite transverse temperature differences in the top plate and negligible transverse temperature differences in the bottom plate of the flat steel-box girder; (2) the temperature probability density distributions of the flat steel-box girder can be well described by the weighted sum of two normal distributions, and its temperature difference probability density distributions can be well described by the weighted sum of two Weibull distributions.