Mechanical behavior for slanting type CFST arch bridge

The Han River North Bridge is a five-span tied rigid-frame concrete filled steel tubular arch bridge without any lateral braces. The maximum span of the bridge is 160 meters, which is the longest arch bridges without lateral braces in the world. Combined with this bridge, some research has been done in this paper to analyze the mechanical behavior of the slanting type CFST arch bridge. Thereinto, the distribution of inner force and principle of cooperation work between the vertical arch rib and slanting arch rib are mainly analyzed. It is found that under vertical load, the slanting arch rib contributes less to the carrying capacity compared with the vertical one; under horizontal load, the two ribs will generate the moment of resistance which can counteract the overturning moment. It is also the reason why the slanting type arch bridge are more stable than the original arch bridge without lateral braces.