Continuous Beam Bridge Cantilever Construction Control

In recent years, transportation in China develops quickly and the amount of bridge increases as well. To across rivers and other lines in traffic, more prestressed concrete continuous beam(PC continuous girder) bridges are required to be built and their main spans are longer and longer. That will bring higher construction technology requirements for them. The cantilever method is the main construction method to built PC continuous girder bridge. But this construction method may make the structure generate complex internal force and displacement, if not carefully to treat them, the bridge construction quality and construction safety will be hard to assured. The construction monitoring control is mostly effective method.Construction monitoring control is around three main basic questions, including the theory design state, construction state and the best realization state. Prior to the implementation of the design scheme, the bridge construction method are set. So we can forecast the completion state and make it as the ideal design state. That is as the realization of the construction goal. And then it uses back analysis method to analyze the ideal construction state and comparing with the real situation. That may get the errors. The control task is to find out the causes of errors and take measures to adjust them in the subsequent construction. Then it uses forward analysis method to get the optimal realized state.Combining with the actual engineering, the construction monitoring control process measures and main work is explained in detail, including:(1) To make clear about several important concepts, including prestressed concrete continuous beam (PC continuous beam), cantilever construction and construction control, analyze their characteristics and master the construction control key.(2) To put forward the monitoring control object and content about being constructed continuous girder. According to the main influence factors and the theoretical results determine control measures.(3) Reasonably to select parameters and establish simulation model using MIDAS/CIVIL for the continuous beam. The calculation results are the theory basis of the construction supervision.(4) In the end continuous beam monitoring control results are given.