Experimental Study And Precision Force Analysis Of The 0# Block Of PC Continuous Box Grinder Bridge

The advantages of prestressed concrete continuous box girder bridge such as the good performance in the situation of bending, torsion and shearing make the structure more stable and safe. In addition, the form of box girder is able to altered to satisfy the requirements of different construction conditions. Therefore, this kind of structure is more and more popular in the bridge construction. However, cracking of the structure is happened in construction stage and period of servicing, this phenomenon not only impact the mechanical property but also bring the esthetic problem of the bridge, and has high risk to lead serious consequence like the collapse of the structure.This paper study for a prestressed concrete continuous box girder bridge, simulated the spatial stress distribution of box girder 0# block throughout the finite software ANSYS, analysed the stress distribution in 0# block of box girder under different conditions.As a matter of fact, the efficiency of the computer calculation effected by the large-scale spatial finite software while its simulated the prestressing duct ins ide the box beam, the reason is that because of the size of the duct is small comparing with the size of box girder itself, to ensured the successful of meshing of box girder, the size of each element must be small enough, therefore the quantity of elements have to be large, so that increas ing the computation burden. In this study, cross sec tion form of the duct is simplified from the circular formation to square and regular octagon. Then obtained the s imilarities and differences of the stress surrounding the duct in different formation of cross section, providing the reference of duct formation design.This study analysed the stress distribution in 0# block of box girder, as well as the tens ile stress and compressive stress of the web plate, diaphragm plate, top and bottom plate of the box girder, finding out the regularities of distribution and the most unfavorable position of bridge in different construction stage; discovering the box girder cross-section mutation and prestressed anchor end position are prone to stress concentration, which results the stress large in some position and then increasing the possibilities of cracking of box girder.This paper analysing and comparing the spatial stress distribution of box girder with prestressed duct and without prestressed duct by simulating PC continuous bridge in cantilever construction stage, summarizing the spatial stress distribution of box girder 0# block influenced by the prestressed duct in cantilever construction stage; analys ing prestressed duct affects the stress distribution in box girder in different position of 1# block of the bridge in detail.Simulating the stage which box girder was completed casting to find out the distribution of stress while that part shows quality defect, obtain the stress distribution in different degree of quality defect and the differences of these stress.In this study, actual measured data of stress in construction stage is collected and disposed, then come out the distribution of stress on 0# block. All those results are analysed and compared with each other.