Abstract: Steel box girder bridge structure is widely used in large span bridges and city bridges. The transportation of dangerous goods and terrorist attacks might have explosive impact on a steel box girder bridge structure. The current various domestic bridge specification cannot provide a concrete guideline about blast-resistant. The foreign bridge specifications also is lack of corresponding detailed provisions. The research group designed a removable blast-load flexible experiment platform for a bridge structure. The scale model of a single box with three rooms is made of Q235B steel from Taiyuan Steel Group. The mechanical properties of Composition B explosive and steel should be calibrated respectively. With the different locations and the same explosive equivalent, the local failure characteristics and global deformation are examined under the nearby blast wave. The failure type of the top plate, the bottom plate and the internal structure are measured through a blast wave propagation process. This experimental design, including a steel box girder, an experimental process and a platform, can provide a verification example for other researchers who are interested in explosive load effects on structures.