Study On Design And Application Of Construction Plan Of Simply Supported Pretensioned Prestressed Concrete T-Shaped Beam With Bent Tendon

Pretensioned prestressed concrete structure with bent tendon is a important form of pretensioned prestressed concrete structure,which bends tendons by bending device before pretension could make the bending moment diagram of prestressed load more close to the diagram of load action,and overcomes the defect of linear pretensioned prestressed concrete members cannot be applied to large-span structure,also solved the problem about poor quality of grouting and prestress out of control fundamentally.In recent years,pretensioned prestressed concrete structure with bent tendon has been applied to multiple fields like cross-sea bridge,highway and railway bridge at home and abroad,but there is not a perfect supporting construction technology,and the existing study of construction mainly focus on the prestressed concrete structure with double bent tendon which bend tendons two times,and the construction of prestressed concrete with single bent tendon lack of study,that has been the mainly reason of restricting the application and extension of the pretensioned prestressed concrete structure with bnet tendon.This paper takes the prefabricated construction of a 30m simply supported pretensioned prestressed concrete T-shaped beam bridge with single bent tedons as background,this project which belongs to the construction project of the highway from Suining to Guangan,this paper study the key contents of the bridge construction,and introduces the construction and application of the T-shaped beam bridge.The main work of this paper:(1)This paper analyzes the key technical of construction of the simply supported pretensioned prestressed standard T-beam with single bent tedons,based on the existing form of tension pedestal to raising a tension reaction system pedestal which could achieve to transfer the reaction forece clearly,simple construction and reusable,also the reaction system could be used to tension the single bent and linear tendons at the same time.(2)According to the requirements of the current designed code designs the reaction system pedestal,then calculates and checks the strength,stiffness and stability of each components of the whole reaction system pedestal,and used the finite element software LS-DYNA to establish the 3-D numerical model to analysis the forced situation of critical part which transfer the reaction force.(3)Construct the 30m simply supported pretensioned prestressed concrete standard T-shaped beam with single bent tedons by the reaction system designed in this paper,through the construction process,tensioning process of the single bent and liner tendon,key point of the concrete construction technology and relaxation process of the prestressing tendons introduces the application of the reaction system.