Study Of Temperature Field Of Concrete Bridge Caused By Solar Radiation

ABSTRACT:Temperature effect has an important impact on the safety of concrete bridge, the temperature gradient modes are not the same in different regions. In this paper, based on the long term observation of concrete specimen and concrete box girder, the temperature field of concrete box girder was studied. The main contents and conclusions of research are as follows:(1)Concrete temperature field varies with the atmosphere temperature change, which are roughly presented sinusoidal variation on a24hour cycle. The temperature of concrete lags behind environmental temperature, and the farther away from concrete surface, lag time is longer, peak of concrete temperature is smaller.(2)Based on long term mearsurment and numerical analysis, suggested formula for vertical temperature gradient of concrete box girder located in Tianjin were proposed, which are different from the current specification.The main differences manifeste in the maximum temperature difference, decay rate of curve and whether the difference of bottom in girder should be considered, the curve suits for other regions of north of North China Plain.(3)Temperature field of box girder was calculated using ANSYS and MATLAB program, and the results indicate that the temperature field which is precise enough in engineering can be got by using numerical analysis.(4)Taking some continuous beam in Tianjin for instance, the effect of solar radiation, daily temperature difference and wind speeds in temperature field were studied, it was found that solar radiation and daily temperature difference are main factors, others has little influence on temperature of concrete bridge.