Span Pc Continuous Rigid Frame Bridge External Prestressing Reinforcement Technology

The researches on the external prestressing technology could be traced to 1970s, however,on the aspects of bridges, the researches were only beginning from 1990s, and they were mostly applied on the consolidation and redevelopment of simply supported beam. These technical applications which were used on the consolidation of long span PC continuous rigid-frame bridge are rare and these kind projects are few to be illustrated. Therefore currently inside the nation the standards corresponding to the designing, the construction and the estimation of the consolidating effects on this kind of technology, do not state clearly. This thesis which is based on real projects, is describing, analysing and concluding the researches on the procedure of constructing on the long span external prestressing PC continuous rigid-frame bridges.This thesis is discussing several problems on the external prestressing consolidation techique, including the arrangment of external prestressing cables, the limitation on control stress, and the appropriate selection on the stress increment;for the supervision on the procedure of consolidation constructing is necessary, the thesis is describing the detail of supervision including methods and giving some instructions pointing to the computing modules on the procedure of construction supervision;due to the large consuming of labour and material on the consolidation on long span external prestressing bridges, the necessity of the consolidation and the estimation on the effect after consolidating will become an important issue. Particularly, through twice load tests that one is before the consolidation and another is after the consolidation, this thesis is deeply discussing and analysing the experimental detail.