Precise Calculation And Software Development For Long Sapn Bridge

The prestressing loss and equivalent load of prestreeed tendon is the main work of circulating calculation in the design of a bridge,whice will directly decides the estimation of mechanics properties of the bridge.The bibliographys provide a few simplified methods, but the research about analytical solution for the anchoring loss and equivalent load of the three-dimension prestreeed tendon is few.Meanwhile,the sofeware for the whole process in the design of a bridge will be advantageous to the application and popularization of the new bridge calculation theories,so it indicates significant research value.Based on the program of simple truss structure,an enlargement has been accomplished,so this paper emphasized on three point:the practical theory of bidge construction stage analysis,the flow chart of the program,the key points of programming.The key points of programming are fully discussed ,such as member with rigid arm,principal -subordinate boudary,temprature change action,the sieving and resetting of nodes in construction circulation calculation,the analysis of creep of concrete and the principle of geometry nonlinear effect,etc.In consideration of the anchorage loss and equivalent load of prestessed tendon which mostly decide the precision of the core calculation, the balance equation of micro-segment in prestessed steel is established based on theory of friction, then the analytical solution of anchoring loss of five-segment-style prestressed tendon is derived according to the deforming coordination principle ,which can be applied to the general case in bridge engineering practice.The calculational method is extended to the multiple segment style prestressed tendon, and the formula is also given while the reverse friction effect length equals the length of the tendon.Then ,the comparison to the results of the formulae in current bridge codes has been finished,which indicates that the analytical solution should be adopted while the prestressed steel comprises largely curved arc; As for the equivalent load of prestessed tendon,firstly,that the flexibility of a spacial prepressed tendon will not induce force is proved and the unfied formula equivalent load is established , based on the principle of the differential geometry, then the result is applied to the curved beam, a comparation is made to the other dissertation to testify the formula, a improved numerical calculation method is illuminated which is more pactical than the traditional and analytical method. The application of object-oriented programming technology in the developing of CCPB is also introdued;In the end,several samples are provided to certify the software.This paper is a summarization of the theory and technology applied in the development of CCPB.