| Composite box girder with corrugated steel webs, which is a new form of structure,can effectively reduce the weight of main beam, and then reduce the work amount ofsubstructure; meanwhile it can solve the problem of inclined cracks in concrete webs.Excessive deflection often occurs on most continuous girder bridges in the process ofoperation, which seriously affected the linear smoothness of bridges and the driving comfort.Therefore, it is necessary to study the deflection.This paper illustrated the development and present research of the design and theconstruction of long-span composite continuous box girder bridge; and introduced thecalculation theory which considers shear deformation deflection, and the mechanisms ofshrinkage and creep of concrete and loss of prestress and their influences on the generationof deflection of long-span corrugated steel webs; besides, this paper established the finiteelement model with Midas civil/FEA, compared the calculated results of civil and FEA,and verified the accuracy of calculation. Lastly, it established the simply supported beammodel and analyzed the impacts caused by different geometric parameters of corrugatedsteel webs on the deflection of composite box girder. Taking a bridge in Xingtai as theengineering background, the author studied the influences on bridge deflection caused bythe shear deformation，the shrinkage and creep of concrete, the loss of prestress, the loss ofrigidity and temperature and vehicle load.Finally, some control measures are offered in terms of design and construction, whichprovides a useful reference for the long-term calculation of effects and observations of acomposite of girder bridge. |
