Research methods: Aiming at the problem that crack often appear; an the end side of box girder for railway passenger dedicated line, the analyses of the cause for crack are made through adopting finite-element computing method and the issues for attention in construction control of box girder are presented.
Research conclusions: The following proposals，made:(1)It is necessary to adjust the construction order involved in Pre-stress and avoid stretching the drill ways of N2a and N1b as much a possible while pre-stretching and primary stretching，conducted; (2) It is necessary to well control the elevation of girder bearing bed and observe the uneven subsidence volume of the bed on fixed time, and if necessary, the measures should be taken so as to avoid appearance of movement of torque; (3) It is necessary to reinforce the structure around the girder lifting hole to avoid appearance and extension of cracks around the hole caused by the large stress while lifting and moving girder, and take some mearsures for keeping the even self weight effects on both ends of girder body w avoid appearance of movement of torque while lifting, moving and lowering the girder.
2007, Vol. 24 
