Research And Practice On Construction Control Of Long-span PC Continuous Beam Bridge By Cantilever Casting

With the rapid development of China's highway and railway, more long span bridges were needed to span great rivers and bays. PC continuous beam bridge emerged as required and has been developed fleetly in recent years. There are a few the construction methods of the PC continuous beam bridge. Among these methods, cantilever installation and cantilever casting have been used widely. This construction method results in the complex change of the internal forces and displacements in the bridge. For ensuring the quality and safety of the construction, the construction control is indispensable.Through the analysis and summary of the development of continuous beam and the developmental tendency of the construction control techniques in our country and abroad, the paper gives the study of the construction control techniques for long-span pre-stressing concrete continuous beam bridge.According to its special character of the construction control, the paper brings forward a reasonable scheme of observation in the course of construction control, and establishes a comprehensive monitoring system. During the construction control of TongLu River Bridge, the system makes the structural displacement and stress of main sections be acquired successfully. And through establishing the computer model, the thesis analyses the difference between theory and actuality, and discerns and changes parameters. Through analyzing controlling methods, the paper uses the method of Grey Forecasting Control to forecast inflection of main beams' deflections. The thesis gives reasonable elevation of formwork to direct construction and joins the two sections of the bridge, and finishes the construction control of the TongLu River Bridge.