Study On Sunshine Temperature Field And Temperature Effect Of Mountains Hollow Thin-Walled High Piers

Hollow thin-wall high piers mountain as the important infrastructure of long-span Bridges in the external environment, under the influence of solar radiation, air temperature and so on, its structure, both inside and outside surface temperature changes, but due to the thermal conductivity of concrete performance is poor, lead to internal and external surfaces of the hollow thin-wall high piers temperature change rate, form a larger temperature difference,and then form a larger temperature difference stress and displacement. Cracks are sometimes caused by temperature stress and displacement is too large, or skew, used cause serious influence to safety and normal operation of the bridge. Bridge damage caused by the sunshine temperature effect is becoming more and more, therefore, an urgent need to study the temperature effect of the hollow pier, to prevent and reduce the damage to the structure. Based on engineering examples as the background, this paper studied is located in the mountains of the temperature distribution and effect of hollow thin-walled high pier. Main work and conclusion are as follows:?1? Through a large number of domestic and foreign literature, in detail introduces the formation mechanism of hollow thin-walled high pier's temperature, the influence factors of temperature distribution and the characteristics of several kinds of temperature load, this paper introduces the calculation of hollow thin-walled high pier temperature field and temperature effect of the method, and the calculation method of solving the heat transfer boundary conditions required for.?2? Introduce the basic information of background of Bridges, determine the field measurement, analysis of high temperature field distribution of the pier, according to the measured data, combined with the relevant specification and theory, with the Mat Lab regression fitting out high pier index of temperature gradient curve, puts forward the suitable for hollow thin-walled pier of the bridge area temperature gradient mode: bridge pier transverse T_x=17.82e^-8.423x ,longitudinal piers, T_y=17.61e^9.428y,and analysis of fitting formulaand the difference of the measured data, accord well with those of display data.?3? Combined with bridge site geographical data and meteorological conditions, using the large general finite element software Midas FEA model hollow pier cross-section temperature, temperature field analysis of bridge pier, contrast analysis and calculation results,the measured data, and the difference of temperature distribution curve fitting method, results show that the three basic consistent, prove the practicability of finite element software simulation. With Midas FEA hollow thin-walled pier of the pier model, analyzes the pier displacement caused by the sunshine temperature difference stress and the sun, according to bridge temperature stress and displacement are large, linear and safety of piers have bigger threat, cannot be ignored. So in the design, construction and monitoring of the bridge must consider the influence of the temperature of sunshine.