| This thesis is based on the construction of Buliu River Bridge, which is a PC continuous rigid frame bridge with span of 145m+235m+145m. The main piers of this bridge are thin-walled high ones, with height of about 95m.Using free cantilever casting construction method to build, this bridge is one of the longer span PC continuous rigid frame bridges in china. With tall piers and long span, the technical difficulty of Buliu River Bridge is obvious. In order to offer useful reference for design and construction of the similar structures, it is necessary to make a systematic summary of these key construction controls adopted by this bridge. Adhering to the principle of combining theory with practice, the major works are made in this thesis as follows.1. The practical methods for geometric and stress control during the construction of PC continuous rigid frame bridge are analyzed combining with the project Buliu River Bridge. This thesis presents the regularities of deflection deformation of box girders in construction by comparing the deflection values of measured and theoretical. In connection with the characteristics of tall and flexible piers, the principle of equipollent prestress load used in this type of structure, the influencing factors of temporary construction loads and temperature effect are analyzed. Some conclusions can be referenced by similar structures'design and construction.2. In stress control, the influence of the reinforcement ration on the restrained effect of the shrinkage and creep deformation of concrete, and the influence of the restrained effect on the cross-section stress are discussed. The effect of the regular reinforcement ration on the cross-section stress is quantitatively analyzed. The measured stress values can reflect the true state of structure by the removing non-stress strain of shrinkage and creep in the measured strain, so that the stress of Buliu River Bridge is effectively controlled. |
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