Research Of The Internal And External Prestressed In Large Span Continuous Ridge Frame Bridge

Along with Scientific technology and the development of transport, prestressed concrete continuous rigid frame bridge with its construction is simple, cost economy, reasonable force, comfortable journey to our unique advantages in recent years have been rapidly rising. However, with extensive use of this bridge, many of large span continuous ridge frame bridge widespread produce cracks in the webs and deflections in the middle of span.This have threated to the continuous rigid frame bridge normal use. The large span continuous rigid frame bridge is designed with a new prestressed system——the internal and external prestressed technique.Make full use of the advantages of external cable can be replaced and repeat Tension, in order to solve or alleviate the current problems.This paper regard the Chong Qing Xitan Qijiang bridge as an example, Research of the internal and external prestressed technique in the large span continuous ridge frame bridge. On the basis of aggregating calculation theory fully, comparedly designing two bridges in background works Project.One is designed with internal and external prestressing, whereas the other is internal. Through comparison analysising, the characteristics of this two bridges are gained. Moreover, the design results meet the requirements of relevant specifications. From controlling ramp cracks, repressing deflections in the middle of span and economy, the advantages of the internal and external prestressed technique has been discussed. At the same time, through implementing external prestressed in this project, the technology and other key points in external prestressed bridge construction have been summed up.In this paper, the relevant research results not only support the design and construction of this background projects directly, but also give a good reference and guide on Building external prestressed bridge in China.