Longitudinal Prestressing Tendons Optimization Of Long-Span Prestressed Concrete Continuous Rigid Frame Bridge

The prestressed concrete continuous rigid frame bridge is a kind of bridge which is nice wholeness, long spanning capacity and beautifully shaped. It contains the characteristics of driving smooth and also has the character of non bearer and construction convenience. Mainwhile, under the vertical load, the negative moment at the cross of girder and pier may make the midspan moment shorter. In a long run, due to the layout of prestressed continuous rigid frame bridge longitudinal prestressing tendons strands depends on the experience of people accumulated, so that the optimization design of prestressed concrete continuous rigid frame bridge longitudinal prestressing tendons is complicated, Therefore, It is necessary to optimize the layout of longitudinal prestressing tendons in prestressed concrete continuous rigid frame bridge. This thesis takes a completed prestressed concrete continuous rigid frame bridge as an engineering example to research the layout of prestressed concrete continuous rigid frame bridge longitudinal prestressing tendons. The main work is summarized as follow:1、To introduce the structure characteristics of the prestressed concrete continuous rigid frame bridge and discuss the development status of prestressed concrete continuous rigid frame bridge at home and abroad and the research significance of this paper.2、Optimization theory and algorithm used in optimization analysis are introduced briefly and the advantages and disadvantages of different optimization theories are compared.3、Elaborating the design method of three dimension prestressing in prestressed concrete continuous rigid frame bridge and the selection of anchorage system for all kinds of prestressing tendons, proposing the analysis and calculation method of prestressed effect in continuous rigid frame bridge.4、A new idea for prestressing tendons type as design optimization variable is proposed, using MATLAB as optimization computing platform, the stress value of each part of the main beam in different prestressing tendons type is compared and obtaining the most reasonable target function of prestressing tendons type arrangement.