Study On The Design And Manufacture Method Of Assembled Steel Box-Prestressed Concrete Composite Beams

Aiming at prestressed concrete continuous rigid frame bridge's shortcomings, such as concrete shrinkage, creep too difficult to control, risk periods too long, Based at what the mentor successively undertake: the national natural science funds projects(51078373)"research on steel box - concrete combination arch structure performance and analysis method"and the western Jiao tong construction technology projects(200631881448)"research on steel box - concrete combination arch bridge vertical rotation design and key technology in construction". The idea"Assembled steel box-prestressed concrete continuous rigid Frame Bridge"is also proposed. Aiming at the specific structure, performance and manufacture method of steel box - concrete composite beams, tests and theoretical analysis are launched, such as:①The preliminary design of relying on engineering"Assembled steel box -prestressed concrete continuous rigid frame" is completed. According to different section girder force needs, choose corresponding combination section form, the superiority of this method on this point is demonstrated. The two materials can give full play to the respective mechanical properties, saving material and reduce its own weight.②In order to make clear the mechanical behavior of fabricated steel box- prestressed concrete combined continuous rigid-frame bridge at negative bending section, a fabricated steel box - prestressed concrete combination experimental beam is designed. The structure size of steel box - prestressed concrete combination experimental beam is drawn up. The ideas of using PBH shear connector link structure between floor concrete and steel box girder, using steel and precast shear key between prefabricated roof and steel box girder are put forward.③Establish a finite element model of steel box - prestressed concrete combination experimental beam. Analyze the transfer characteristics of steel and precast shear connector. And put forward a simplified calculation formula of shear capacity of steel and precast shear key applied in experimental beams.④Prefabricate perfusion material for S&P shear key pre-setting hole, it is successfully applied to the experimental beams manufacture. Explore the mix proportion design method of experimental beam and real bridge's perfusion material. Also put forward a set of construction methods suitable f-or assembly steel box - prestressed concrete composite beams when pouring materials. ⑤Given construction control requirements for composition beam in manufacture process. Analyze the main cause of appeared making errors of experimental beams in the test. Discuss the influence of these making errors on structure properties.