Studies On Temperature Effects And Its Influence On Stability For High Pier With Thin-Walled Hollow Sections

With the development of China's expressway and high-speed railway, a great deal of high pier long span birdge will be used in canyon areas.. It means, the pier's stiffness will be weaken. So bridge'whole stability will be weaken too, especily during the constructing stage. And the degree of sensitivity about external environment will be increased. Such as variation of environment temperature, solar radiation, gust and so on. Because of long constructing time, the environment temperature's influence on high pier's stability during constructing stage must be pay attention to.In this thesis, on the basis of studing on temperature distribution mode and temperature stresses for high pier with thin-walled hollow sections, parallel with construction of XianShenHe bridge, the temperature gradientcurves about 150.07m high hollow octagon pier and 97.5m high double-column pier are measured and analyzed. The estimate formula for those high pier be brought up. With this formula, the calculation result agrees well with the measured data. Based on heat transfer theory,the mechanism of heat transfer between high pier and external environment be researched. The ANSYS software is re-developed on the basis of solar radiation and heat transfer theory. By using language APDL, The command lines of calculations about temperature gradientcurves, temperature stress and temperature deflection for high pier with thin-walled hollow sections be written. . The commond be inbuilted in ANSYS interface by means of interface language UIDL and TCL/TK. The result of temperature gradientcurves ,temperature stress and temperature deflection about high hollow pier be computed. The program had the functions for pretreatment and aftertreatment. can be used for high pier of any shape and any size with different geography longitude and latitude, different bridge's azimuth angle and wind velocity. The program is used to analyze temperature gradientcurves about XianShenHe bridge's high pier of JinJi High Way. And the computed outcome agrees well with the measured data. Meanwhile,the results also show that the temperature stress is quite large.Based on the work mentioned above ,the temperature influence on stability of high pier bridges has been studed ,According to its result, more attentions should be paid to temperature effect on stability of high pier bridges. At last, the geometric nonlinear's influence on high pier's stability is discussed,and the measures to increase stability of high pier bridge is suggested. The temperature influence on monitoring and controling for high pier bridge construction is also discussed, which is referencable for those kinds of works marized.