Test Research On Temperature Field Of Hollow Pier Of Xing Fu-yuan Reservoir Major Double Track Bridge

With the rapid development of bridge construction, the bridge span becomeslonger and the pier becomes taller and thinner than before. Because the environmentaltemperature changes all the time, these huge bridge piers would produce thermalstresses and causes serious economic losses. By working hard for half a century, peoplehave known well on temperature field and wrote the results to standard. It states veryclearly about the temperature field and thermal stress of box girder in the standard. Butthere’s no exact illustrations about temperature field of pier. So, in order to satisfy theproject needs, we must research the temperature field of pier immediately.This paper, supported by”Technology Research on High Pier Sructrure Design ofMountain High-speed Railway Bridges”, with engineering back ground of XingFu-yuan reservoir major double track bridge, combined with model test, studies thetemperature field of hollow pier and the influence of reinforcement ratio to thetemperature field.In this experiment, it builds one scale model whose size to the prototype of bridgepier ratio is1to10and three section models whose size to the prototype of a part of pierratio is1to1. And, the section models have six different ratios. To research on the totaltemperature field in the pier, it tests the temperature of scale model when it is heated inthe sunshine or heated inside of itself as simulation of the cold wave. In order to studyon the laws about temperature changing along the wall and the influence ofreinforcement ratio to the temperature field, it tests the temperature of section modelsunder the solar radiation. Meanwhile, it uses finite element software to check the resultsof test. By testing the temperature of scale model and section models and usingleast-squares method to analyze the test results, the paper gets the followingconclusions:①Because of the solar radiation, the temperature difference between eastern innerand outer wall reaches the maximum at11:00and the temperature difference betweenwestern inner and outer wall reaches the maximum at6:00pm. By contrast, thetemperature difference between western inner and outer wall is bigger than eastern,which is more unfavourable. When heating inside the model, it turns out that thetemperature difference between inner and outer of south wall is bigger than other threewalls, which is more unfavourable. ②The temperature contrast curve in bridge pier generated by the effect of sunlightor the effect of lights heating inside the pier is an exponent bight which can beexpressed as this equation:T_y=T_0y·e^-ay③Because the temperature contrast in scale model affected by the height of pier issmaller than the thickness of wall, it can be ignored when analyzing the thermal effect.④Under the conditions of the experiment in this paper, the reinforcement ratiohas little influence on the temperature field.