The Key Technology Of Flyover Swivel Construction

Since the 21 st century,China's economic and transportation construction has been developing rapidly,thus raising higher requirements for road construction methods and standards.Many roads and bridges must cross the valleys,traffic lines,deep rivers and other areas difficult to construct.Especially when it is necessary to cross the railway lines which cannot be cut off,the bridge swivel construction is needed.Bridge swivel construction is a bright construction method.The bridge is not constructed on bridge design axis,but on the position offset or parallel to bridge axis where firstly the main bridge is constructed via the cast-in-place concrete and precast splice etc.When the main bridge construction is completed,it is rotated to the designed bridge position with the pre-construction rotation power device,and finally is closed.Through participation into the whole process of construction technology,process,organization and related measures of flyover swivel construction crossing Jingha Railway,Jinshan Railway on the Qianxi branch of Beijing-Qinhuangdao Expressway,the in-depth study,analysis and summary are made,thus to provide theoretical data support and related construction experience,and to provide valuable experience for the similar bridge constructions in the future.Through theoretical study and practice,the key part of the plane swivel bridge is the construction of the rotating system,wherein the rotating support is the key link in construction.Meanwhile,the structure is able to rotate and facilitates rotation,only by reducing structural frictional resistance,increasing rotational torque and staying continuous horizontal rotation.And on-site counterweight must be conducted so that the center of gravity locates in the center of supporting pin and ball hinge,and the structure reaches a stable state.