Study On The Effect Of Temperature Gradient Of Concrete Tied Arch Continuous Beam

Bridge is built across natural or artificial barriers and building, with the development of science and technology, more and more composite structure applied in the modern bridge. Tied arch continuous beam bridge as a combination of the advantages of beam bridge and the arch bridge, the advantages in terms of stress can be brought into full play, showing the economic indicators and beautiful appearance, stable quality. Although the beam arch combination bridge has many advantages, but for research and discussion on the bridge is not perfect, many problems are found by the Chinese and foreign scholar research. The effect of temperature, as in recent years, more and more attention to this problem, since the sixty’s of last century some scholars have study it, the temperature stress cold sometimes equal to the external loads, temperature effect will directly affect the safetyof the bridge. In order to verify the temperature of tied arch continuous beam, this paper takes the actual project as the background, the concrete tied arch continuous beam bridge site temperature test. Tied and boom around the layout of temperature measuring points, measuring temperature of seven consecutive days of observation. The measurements include temperature variation tied vertical and transverse variation of ambient temperature and the rule of measuring point, and through the observation of the tie bar temperature, using the semi theoretical and semi empirical formula to fit the tie bar in vertical and transverse temperature gradient finally according to the derived temperature gradient is equivalent to linear temperature gradient, the temperature load applied in the form of MIDAS finite element model of the whole bridge, to study the temperature effect of tied arch continuous beam.This paper first describe the analysis theory of bridge structure temperature field and calculation method, the temperature effect of classification and its influence on bridge structure; rules on temperature gradient calculation theory and the specifications of different countries and introduce the effect of temperature. And then through the analysis of the measured temperature data, find the distribution rule of the tie bar and rod, and selects the piecewise function to the unfavorable vertical and transverse temperature distribution fitting. At last, by using the finite element model of the bridge in the vertical temperature gradient, transverse temperature gradient and the effect of the combination, through the analysis of internal force of the control section and the stress produced by the temperature gradient, found that the temperature stress and deformation couldn’t be ignored; and compares the standard of temperature gradient to the vertical temperature gradient regulating temperature the effect of the temperature gradient effect, found that, the main control section internal force and stress is smaller than the standard.