Research On The Disease Cause Of Concrete Bridge From Pre-Stress Loss

With the development of science technology and traffic enterprise, the continuous girder bridge ridge has been growing up rapidly in the recent years with it's unique predominance of handy construction, economical cost,reasonable internal force and comfortable traveling. But the theories and experience in it are not very perfect because of it's short appearance. There are still several questions in the construction. The paper introduced the importance of prestress losses and its determination in prestressed concrete structures.In recent years the genetic algorithms has become a Striking research topic in china and abroad. It is generally believed that development in this field will bring significant outcomes and great promise for application. Relying on the Zhongxiang bridge, in this paper a genetic algorithm is applied in identifying the pre-stress loss of the long span bridge. A model with some parameters is made to assess the pre-stress loss. Based on several obvious characters on the disease of the bridge to determine the cause of the disease, the model parameters are identified by the genetic algorithm, and the pre-stress loss values of different sections are given. It is demonstrated that the genetic algorithm is efficient and the theoretical results fit well with the disease.Otherwise,in using the continuous girder bridge we can find that the craze of the box-beam is very popular.The same phenomenon occur on the the Zhongxiang bridge,either.Through analyse,we can find out it's lack of the principal stress on the inclined section cause the craze.It's indicated that the vertical stress is the key to resist principal stress and shear stress by the theory and practise.So the amount of the vertical pre-stress loss is one of this paper's aim.This paper make a deep analyse on the cause of the inclined crack on the transverse beam of the box-beam,especially the effect of the vertical pre-stress loss.It offers the credible scientific according for the constitute of the project on father of the bridge.In this thesis, simulate pre-stress loss of the bridge, aim to anastomose the value of the sink to the distortion after the pre-stress loss of the bridge, genetic algorithms is applied in the identification on diease cause of prestressed concrete continuous girder bridge. It is successful for used in girder bridge. On the bridge diease cause, attempted a new method.