Experimental Design And Study Of PBL Stiffened Concrete-filled Flat Steel Box Slab Arch Bridge

PBL Stiffened concrete-filled flat steel-box slab arch bridge is a new type of composite bridge structure. The composite structure is formed by setting inner perfobond ribs and filling concrete into these boxes. The mechanical property and the main structure form of this slab arch bridge have been studied by FEM. The work has been done in this research and the conclusions drawn from this research are listed as follows:(1)Research status and typical application of concrete-filled steel tube in arch bridge have been stated, the achievement and defects of recent research on PBL connector and rectangular CFST have been concluded in this paper. For instance, the calculation method of shear strength of PBL connector, structure type of PBL stiffening rib and the design method are undefined.(2) Due to the big flakiness ratio, the stress distribution in cross direction of the slab arch caused by the column structure is needed to be taken into consideration. Abaqus has been applied to analyze the cross-section stress distribution of slab arch with different flakiness ration under concentrated force, thus, in some degree, guidance has been provided for the design of slab arch bridge.(3) The effect to the structural mechanic behavior of slab arches influenced by different types of cross-sections, axis of arch, rise-span ratio and some other parameters have been compared and analyzed based on Midas/Civil, and the design checking of such structure under construction and being completed has been done, and the reasonability of this kind of structure has been proved in mechanic ways.(4)Considering the peculiarity of big flakiness ratio of cross section in slab arch bridge, the core mission is to decide the lateral allocation of boxes and ribs. The longitudinal and vertical shear strength of PBL has been analyzed by Abaqus, and the reasonable perforation form has been stated, considering shearing strength on different axis.(5) Compared with common ribs with the same geometric size, PBL ribs’ stiffness has degenerated in a way. The conclusion drawn from analysis according to Timoshenko method and FEM manifests finds that the reduction factor of buckling stress when the structure is reinforced by flexible ribs is bigger than when it is reinforced by stiffed ribs.