Construction Control And Temperature Effect Of Long-span PC Continuous Rigid Frame Bridge

As the important part of modern construction technology, construction control is playing a more and more important role in the successful erection of long-span bridges. Because the balancing cantilever segmental construction method has been widely applied in the building of long-span continuous rigid frame bridge, it is necessary to execute a construction control effectively to ensure the structural safety, successful closure of a span and the ideal alignment of superstructure during and after erection of the bridge. In this thesis, a grey predictive control system for one construction control of long span pc continuous rigid frame bridge has been developed from the grey system theory and the modern predictive control theory, and the system has been applied on the construction control of Baishui Bridge across Xiangjiang River in Qiyang that is a PC continuous rigid frame bridge with two main spans of 120 meters to predict and control all construction states. It has been proved that the application of Grey predictive control system can ensure construction safety, make ideal alignment of superstructure and the internal force of Baishui Bridge after closing-join to meet the design requirement successfully.The stress caused by sunshine is an important part of reaction of PC box girder and it is crucial to have a certain temperature field to determine the temperature effect of the PC box girder bridge. Based on the 24 hours continuous observation on the temperature filed and the corresponding effects of the Baishui Bridge during and after its construction, a simplified temperature gradients pattern is put forward, the effect of temperature difference on the PC continuous rigid frame bridge is thoroughly analyzed on the base of the temperature gradient, and the calculating results agree well with measured ones, which demonstrate the temperature gradientmodel presented here is feasible.When Baishui Bridge is closed join at high air temperature, the internal forces in the structure caused by the higher temperature difference are analyzed, and a reasonable measurement has been put forward to ensure the bridge closed successfully in the higher air temperature.