Study On Temperature Effect Of Environmental Factors For PC Pylon Of Cable-Stayed Bridge

For PC cable-stayed bridge, the weight of the girder and live load role in the towerthrough the cables, so tower is the core component of cable-stayed bridge. The towerexposures in the natural environment all the time. It’s affected by the solar radiation, coldwave, and other inclement weather. Because the thermal conductivity of concrete is poor, thetower will produce an adverse temperature field, appear great temperature stress and evencause cracks on the structure surface when it is serious. Currently, the study of bridgetemperature field is mainly concentrated in concrete box girder, but less on the tower.Therefore, it is necessary to do research on temperature field and effect in tower.The reasons for the formation of structure temperature field are divided into external andinternal factors. This article is based on the Guangzhou Bridge in Meizhou city as theengineering background. It do research in the analysising of external factors (externalenvironment factors) on the degree of influence of the temperature field and the effect oftower from wind, orientation of the bridge tower, and transparency of the atmosphere.Cable-stayed bridge pylon is a vertical structure with the highest height of300meters inChina. Wind speed is the main reason affecting the temperature field. Because wind speed isdifferent in different heights, there are different temperature fields in different heights of thebridge tower. Through the analysising of temperature field in different wind speed of lowtower and high tower, we can see the degree of influence of wind speed on the pylontemperature stress. In addition, the different directions of tower will cause the different sunnysides and different sun angle. Based on the research, it comes to the most unfavorableorientation of the bridge towers. The transparency of the atmosphere determines the size ofthe solar radiation intensity. When the atmospheric transparency is the highest grade, solarradiation is strongest, the bridge tower will produce the most adverse temperature field, andalso with the most disadvantaged force.