Launching Trajectory Planning for the Variable Cross-Section Steel Box Girder

Abstract

The incremental launching method has been widely used to construct various kinds of bridges in regions where traffic, geology and topography conditions are limited. Thanks to its excellece on on-site prefabrication, fast assembly and intelligent control, the incremental launching systems are applied in mumerous kinds of bridge construction projects. However, most of the bridges are successfully built without having the obvious curve features on working interfaces. This paper mainly proposed an adaptive incremental launching method for the Dongfeng Avenue freeway L7 89m viaduct launching project, to which the traditional incremental launching method is hard to be applied. Firstly, the construction background is firstly introduced. Then, the corresponding launching trajectory is planned according to the continuous variation of curve features of the working interfaces. To realize the launching trajectory, the control stratege and kinematic conditions of multi-point on-site incremental launching devices are described. Further, the application and verification of the launching construction are analized and discussed. Finally, the proposed new incremental launching method and the results of trajectory planning for the variable cross section steel box girder are concluded. Keywords-incremental launching; bridge girder; launching trajectory; curve feature