Study Of The Construction Control Techniques For Long-Span Prestressed Concrete Continuous Beam Bridge

Because of the complicated construction procedure of the long-span bridges, the bridges will be affected by many certain or uncertain parameters, so that the actual construction state of the bridges might deviate from the state of theoretical design. Therefore, the bridge construction control emphasizes the deviation-identifying and analyzing, the Problem-finding out and error-adjusting in time, and state-predicting for following construction, so as to guarantee the construction system under control all the time.Firstly, this thesis introduces the construction control contents and methods, basic principles for long-span continuous beam bridges. According to the construction control characteristics of long-span PC continuous beam bridge, the thesis brings forward a reasonable scheme of observation in the course of construction control, and establishes a comprehensive monitoring system. During the construction control of West-tributary Supergiant Bridge with Ganjiang River, the system collects the structural displacement and stress of main sections successfully. And through establishing the computer model, the thesis analyses the difference between theory and actuality, and discerns and changes influential parameters of bridge-analyzing. Secondly, the thesis uses the method of Grey Forecasting Control to forecast inflection of main beams' deflections, giving reasonable elevation of formwork erection to direct construction, and redacts a program to calculate inflection of main beams' deflections during the construction. Thirdly, the principle of strain measurement is described, combined with engineering application and case study, several primary factors are analyzed based on theoretical computation and actual measurement with the vibrating wire sensor in West-tributary Supergiant Bridge of Ganjiang River. Finally, loading-carrying ability of design is certified through the load test.