Study On Technology Of Bond- Retarded Prestress In Bridge Engineering

As a new type of pre-stressed technology,the delayed bonding prestress technology,which combines the advantages of two kinds of non bonded prestress and bonded prestress,overcomes the shortages of the two technologies.Slow bonded prestressed technology of unbonded fat instead of to retard bonded materials, corrosion materials bonded early solidification, along with the age growth gradually hardened steel strand and concrete bonding together, and finally becomes similar to that of bonded steel strand. Thus, the early construction is convenient, the use of the latter safe and reliable, is a very promising technology of prestressing.Slow bonded prestressed concrete structure mainly includes the retard bonded prestressing tendons and concrete structure, the paper focuses on the corrosion characteristics of bonded prestressed concrete structure, slow bonded prestressed tendons,retard bonded prestressed technology, research binder and large diameter steel strand corrosion.Firstly,the working principle of the delayed bonding pre-stressed structure is introduced, and the characteristics of the delayed bonding pre-stressed structure are analyzed.. Based on this, the corresponding design and construction calculation method is established, which lays the foundation for the application of the retard bonded pre-stressed system..Secondly,to slow bonded prestressed tendons based introduced slow adhesive(including retarding mortar gentle curing resin), and the mortar gentle curing resin of slow coagulation mechanism were discussed.Based on the studied retarding mortar gentle curing resin,according to outsourcing mortar type slow bonded prestressed tendons and outsourcing resin type slow bonding prestressed tendon structure and principle, of two slow bonded prestressed system are analyzed and compared. At the same time, the mechanical properties, friction factor, physical property and stability of the binder are also analyzed.. Analysis of unbonded prestressing tendons stretching resistance slow bonded prestressed concrete beams in.Then introduced large diameter prestressed steel strand, through structural analysis of large diameter prestressed steel strand, and the combination of large diameter prestressed steel strand and slow adhesive characteristics, combine the two, the study proposes a new type of prestressed structure.Finally,combined with the characteristic of Guangxi Guigang to longan new highway engineering, and combined with the slow bonded prestressed technology’applicable conditions, take a bridge in a Highway Engineering in Guangxi as an example, using slow bonded prestressed technology of prestressed box girder of optimization design, and analyzes the corrosion bonded prestress technology economic benefit and social benefit.