| In recent years, as the country's economic developed, China has established a considerable number of large-span prestressed concrete bridge. This part of the bridge with the establishment of long-span prestressed concrete bridge caused attention by the engineering to the temperature effects and creep effects. Although the temperature effects and creep effects in concrete bridges have made great progress in research, the two time-varying effects of coupling is not really carry out in system,and research the joint application of the bridge is not conducted.This paper summarized the current concrete structure, especially highway bridge, in the temperature and creep research.And summary creep mechanism and influencing factors. Relying on the western project " Study on concrete bridge coupling of time-vary ing effects (contract No.2009318812069)",Yan'an Shi Wanghe River Bridge as the engineering background, sampling done through on-site test specimen, the measured data related to creep and the prediction model comparing with the measured values and predicted model, obtained theoretical value has the same trend with measured. In 04 standard and ACI specifications submitted creep coefficient is bigger than the measured, CEB-FIP creep coefficient specification is too small.measured the box-girder cross-section temperature distribution under the solar radiation, obtaining Shi Wanghe River bridge box girder fitting curve of vertical temperature distribution. The use of MIDAS/Civil, will be comparated analysis in on-site measurement of the temperature gradient and Highway bridges and culverts designed to general specification (JTG D60-2004), and draw some large temperature difference applied to useful conclusions in arid regions of northern Shaanxi. Application of MIDAS/Civil for the whole bridge model of temperature factors and the creep factor in their impact on the concrete structure, and compared the measured value. Effects of temperature and creep deflection theory actual values of the stress have similar trend, but the theoretical value is less than the measured value. Analysis indicates that between the existence of stress on the structure of the nonlinear coupling. With the bridge span and the use of time increased, Under the influence of the couplingthe concrete continuous rigid frame bridge deflection under constant torsion, the stress is increasing, and far exceeds the calculated theoretical value. This occurred during the bridge operations caused by bad alignment,it made passengers feel uncomfortable, and in severe endanger road safety.This coupling effect on the temperature creep characteristics of the analysis carried out coupling, It is the first consider creep effects and temperature effects of the coupling Effect. And established considering creep effect and temperature effect of coupling parameters. B3 creep model of the amendments introduced in the coefficient of temperature T has reached a new creep and temperature coupling formula. In this paper, coupling effect of temperature and creep studied is to start from the theoretical calculations, analysis and calculated in concrete temperature creep coupling stress and deflection of the bridge structure, the impact can draw relevant conclusions reached to amend the coupling formula, and makes the calculation more precise. Calculated by studying aspects of theory, analysis and calculation, temperature creep of concrete on the bridge structure coupling stress and deflection is draw relevant conclusions, coupled correction formula to calculate is more accurate. Error changed from 30% of 10%, coupled theoretical results closer to the actual project status.
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