Researchs On Some Questions Of Healthy Diagnosing Of Long Span Bridges By Surveying

The geometric figure, internal force and stress of the long span bridge will be affected by not only external factors such as traffic load, wind force, temperature difference and earthquake, but also internal factors such as concrete contraction distortion, flab of reinforcing steel bar and foundation settlement of bridge's frusta or platform. In order to make sure that the working safety and endurance of bridge designing, especially the big long span bridge, meet the expected designing standards, it is very important for us to real-timely understand its healthy conditions.The variation of the bridge's space position (i.e the structure of deformation) is a more integrated index and also an easily-monitoring quantity in reflecting bridge's conditions. It is an important method guaranteeing the bridge safety by monitoring the structure of deformation to grasp its healthy conditions. The healthy conditions diagnosing by surveying is to monitor from all directions, the space position of the bridge's major parts by using principles, technique and method of engineering surveying and special precision engineering surveying.This paper, according to the cause of long span bridge deformation and its deformation quantity, firstly discusses the monitoring contents and monitoring methods and detailedly introduces the means used in static monitoring and dynamic monitoring of bridge structure, and analyzes and compares the applicability of every means in monitoring of the long span bridge. The long span bridge includes Arc Bridge, Continuous Rigid Frame Bridge, the Cable Stayed Bridge and the Suspension Bridge and the content of scheme designing of long span bridge includes monitoring content, the method of monitoring dot distribution, monitoring precision, monitoring periods and related methods. The above-mentioned contents are discussed in details in the paper so as to ensure that the monitoring is safe, economical and credible and its scheme designing is the best.Finally based on the designing scheme of healthy conditions monitoring of HaiCang Bridge, the GPS RTK data from it are processed. Considering the data of GPS RTK are easily affected by not only multi-path error and signal interference, but also meteorologic factors,...