Finite Element Analysis On The Static Performance Of Concrete-filled Thin-walled Steel Box Pier Column Stiffened With PBL

As the bridge engineering technology is reforming rapidly, design span of bridgestructure keeps increasing, and pier height records constantly being refreshed. Under thisbackground, study on the new type of pier column structures has become an urgent andvaluable issue. Based on the study of the mechanical properties of concrete filled steel tubularstructure and the fact that steel box columns are easy to buckle, we proposed the PBLstiffened thin-walled steel box concrete pier column structure. After doing many field tests, aseries of studies were done by using the ABAQUS finite element analysis software, getting alot of useful results. The major researches are as follows:Firstly, focusing on how to do the finite element simulation of the PBL stiffenedthin-walled steel box concrete pier column structure. The emphasis was of the simulationmethod of the PBL stiffener, and the simulation of the interaction relationship of steel box,core concrete and the PBL is also a difficult problem. In order to get an accurate finiteelement analysis model, we had to adjust the model parameters based on the test results.Secondly, analyzing the finite element model of axial compression short columnstructures, simulating the ordinary steel box concrete structure and steel box concrete shortcolumns structure with longitudinal stiffened ribs as contrastive models. Do further study onthe mechanical force-transmission mechanism and failure mode. In order to make evaluationon the stress superiority, we analyzed the mechanical properties of the steel-concrete interface.Do analysis on the limit capacity, while parameters of PBL stiffened steel box hole-openingrate are changing.Thirdly, we established the finite element model of axial compression short columnstructures of PBL stiffened thin-walled steel box concrete, studying on the structuredeformation, stress nephogram, stress path curves Also, compare the ordinary steel boxconcrete structure and steel box concrete short columns structure with longitudinal stiffenedribs, so that we can know more about the stress mechanism and failure mode. We get themechanical properties of various long column models by setting load displacement curve,strain curve, ultimate capacity curve, and ductility index. we did further study on the effectsof slenderness ratio on failure modes.Fourthly, Take a high pier belonging to same continuous rigid frame bridge as theprototype and brief design the hollow pier stiffened by PBL, Make full use of the symmetry,established1/8segment veneer model of the pier，verify the above analysis process. Analyzethe mechanical properties of the component whole, the steel-concrete interface, the stressmechanism and failure mode. The results of this paper can provide reference for the practicalapplication of the new structure.