The Study Of Multispan High-low Piers Continuous Rigid Frame System And Construction Monitoring Methods

Continuous rigid frame bridge with continuous girder bridge is not only advantage without expansion joint, driving smooth and comfortable, and both T rigid frame bridge without support and system transformation. It also has its unique advantage in economic indicators. Mountainous terrain ups and downs, multi span height of pier continuous rigid frame bridge is decorated can adjust measures to local conditions, across the deep ravine, flexible, high piers at the same time push the stiffness is small, has good adaptability. With the rapid development of bridge construction, in service or under construction of large span prestressed concrete continuous rigid frame bridge has become increasingly grow in quantity. But many Bridges due to congenital defects caused serious threat to the follow-up operation safety. In order to ensure the quality of bridge construction and the safety during construction and operation process, bridge construction monitoring become must link in the construction stage.The paper is based on Hezhang bridge in Guizhou freeway, makes sure the bridge scheme and bridge pier type. Finally the construction monitoring plan was carried through. In this paper, the main content includes:① The bridge cite is in a trench deep valley. The plans of prestressed concrete continuous rigid frame bridge and prestressed concrete with cable-stayed bridge towers are designed for the terrain conditions. Two plans are compared by the construction convenience, engineering cost, construction period and custody. The prestressed concrete continuous rigid frame bridge is determined as a bridge scheme on the implementation of the construction drawing.② Aim at the 195 m pier height, we design the whole picture of single box 3 rooms and lower for the whole box of nine rooms, two piers forms for upper limb thin-wall piers. The maximum cantilever state stability coefficient and displacement are compared with the two methods, the calculation analysis of the whole picture of single box 3 rooms for bending and torsion stiffness, good stability and can satisfy the requirement of structure deformation and stress. The whole picture of single box 3 rooms plan simple structure, less investment of human and mechanical equipment, construction is easy. Finally the scheme of a whole picture of a single container 3 rooms is adopted as the highest pier construction drawing design.③ Cantilever construction monitoring of the bridge with a focus on the structure of the linear monitoring and stress monitoring. Through the special analysis software calculated in advance and girder deformation as a result, combining the existing deformation is analyzed, in order to determine the next segmental construction formwork elevation, eliminate the deformation of existing and projected in a timely manner. To monitor the key segment elevation and stress, and finally to the key into the state of the bridge deck line and the cross section stress of the last survey, construction monitoring program to verify whether the results meet the requirements.