Research On Key Technology Of Construction Monitoring Of A Self-anchored Suspension Bridge

In recent years, there have been a variety of landscape bridges which have beautiful shape and able to represent the spirit of city in our country with the rapid development of bridge construction. Self-anchored suspension bridge which is considered to be a bridge type with special and beautiful shape, simple and reasonable force structure has become the most competitive in the medium and small span landscape bridge program by attention of more and more designers.The self-anchored suspension bridge is so peculiar that it can not completely meet the structure stress principle in structural design and need to cooperate with the construction supervision in the construction stage for ensuring the stability and safety of structures. So this dissertation focuses on the construction monitoring of a self-anchored suspension bridge during the whole construction process and combined with monitoring theory and model calculation to conduct a comprehensive analysis and study of internal force and geometric distortion of the bridge structure at each construction stage and ensure the finished bridge state as same as the design goals. The practical and valuable research achievements have provided effective technological support to the accomplishment of the bridge and accumulated experience for the construction of such a bridge type.The main contents and results are as follows:(1) Literature review. According to a lot about self-anchored suspension bridge information and construction monitoring technology, the development history and current status as well as the basic structure, force and construction characteristics of self-anchored suspension bridge are understood. At the same time, the relevant information of bridge construction monitoring technology is finished. On this basis, adapted to the tasks, method and key points of monitoring of self-anchored suspension bridge is clear.(2) Research on the main cable of self-anchored suspension bridge with a practical project in the initial state theory of alignment and bridge state of real linear. The empty cable shape finding work is completed by using finite element analysis software, and then the empty cable shape can guide the construction of the main cable. The finished bridge state of main cable state is comprehensive judged by comparison between the design of the bridge alignment and the actual monitoring data of linear bridge state. And then the possible causes of error should be found in order to provide a reference for the future construction of such cable.(3) Research on key monitoring technology of main beam during main construction phase. The theory value of camber is calculated by using the software and as a construction check basis in steel box girder welding assembly stage. During the beam jacking and falling process, the beam force which is uniform and reasonable and the deck line which meets the design goals are analyzed and judged with using hierarchical construction scheme, executing close monitoring step by step, combined with steel roof and bottom plate stress change rule and the changes of the bridge deck line. The conclusion is that the internal force and the altitude of beam always meet the construction precision and the design requirements.(4) Research on dual control technology of the main tower. In order to ensure the main tower balanced stress, deformation coordination, safe and reliable, the geometric deformation and stress of the dual control measures should be used because the main tower of the project is strange and tilt backwards. The internal force and deformation of main tower is comprehensive analyzed through the finite element analysis software simulation of single tower under dead load and combined with the actual monitoring data. The deformation of main tower which is included gravity and caused by the main cable construction has been well controlled and met the design requirements.