MECHANICAL PROPERTIES OF LONG-SPAN STEEL BOX GIRDERS UNDER WALKING INCREMENTAL LAUNCHING CONSTRUCTION

The incremental launching construction technique has been widely used in bridge construction due to its low requirements for bridge foundations and construction spaces, and still high construction efficiency, etc. To date the walking incremental launching construction technique for steel box girders of long-span bridges has been studied by finite element simulation or analyzed by construction monitoring data, and few studies combined these two. Based on the Xiabulong Bridge, a finite element model using MIDAS/Civil was modelling to simulate its mechanical properties under representative construction stages, including stress of the most unfavorable section for the steel box girder in eath constrution case and the displacement of the guide beam front end, and the monitoring data from the field test were used for comparative analysis. The results indicated that the stress state of the steel box girder cross-section and the maximum displacement of the guide beam front end calculated by the FE model were in good agreement with the actual construction data, and the errors were less than 15%.