IN-PLANE BEARING CAPACITY OF HIGH-STRENGTH CONCRETE-FILLED STEERL TUBULAR ARCHES

The symmetrical step loading was carried out on six high-strength concrete filled steel tabular (HS-CFST) parabolic arch specimens. The mechanical behavior of the arch rib under a uniform load was investigated, and the ultimate bearing capacity of HS-CFST were also obtained. The experimental results are compared with the FE results, showing a good agreement. Based on the parameter analysis of finite element model of the arch, the effects of the steel tube strength, of concrete strength, of rise-span ratio, of slenderness ratio and, of steel content on the in-plane bearing capacity were analyzed. The results show that the ultimate bearing capacity of the arch rib increases with the increase of the strength of the steel tube and concrete, and of rise-span ratio and steel content, but decreases with the increase of slenderness ratio. When the strength grade of the steel tube increases from Q460 to Q690, the bearing capacity of arch rib increases by 19.4%~21.4%. It is also found the rise-span ratio, slenderness ratio and steel content are the main factors affecting the in-plane bearing capacity of arch ribs.