Study On Temperature Effect And Cable Force Test In Construction Control Of Cable-Stayed Bridge

With the development of long-span bridges, the construction control plays an increasingly significant role on the cantilever construction of cable-stayed bridges. This thesis researchs on the critical factors influenced on the accuracy of construction control in the two aspects.Temperature effects: Combined with the construction control of Sutong Yangtze River Highway Bridge, the thesis firstly presents briefly the calculation method of concrete bridges' temperature field caused by the sunshine, based on theories of concrete structures' heat conduction. Then according to the measured data fitted the pylon section of the temperature field, obtained the most disadvantaged temperature distribution in the location of Sutong Bridge. In addition, the pylon section temperature distribution at night is researched on when the key conditions for the construction are going on , the results showed that during the night in a cooling pylon the temperature distribution is different from the standard, temperature distribution at night has not suited for distribution of exponent , the thesis presents that it is suitable to use three times curve fitting , the calculated results of the fitted temperature field can satisfy the requirements of construction control. As to the temperature distribution on cable, measured data shows that the temperature distribution is not uniform, temperature difference exists along the section, the thesis derived more scientific and rational cable equivalent uniform temperature. According to the front derived temperature distribution, application of large-scale nonlinear finite element software NLABS, temperature effect analysis on the pylon, girder and cable is done, and have a study on the effect of temperature and process of the temperature effect of a sensitivity analysis, which provides a scientific foundation for reasonable consideration temperature effects during construction control.Cable force testing: the cable testing frequency is studied and the first equivalent band frequency is obtained, which can better reflect the true cable force. the ANSYS modeling is set up and a dynamics analysis is done,which provides a scientific basis for acquiring accuracy of the cable force.