| As composite constructions, the concrete-filled steel tubular (CFST) columns areformed by infilling concrete thin-wall steel tubes. By dint of steel tube's restrictions,the interior concrete lies in press conditions in three principal axes directions, whichdelays lengthways cracks'developments. Consequently the interior concrete takes onpreferable compressive strength and great compression deformation capabilities. Invirtue of larger carrying capacity, lesser in sectional dimension, lighter in weight, higherductility, shockproof, fatigue resistivity, saving in material and convenient construction,it has been extensively used in high-rise, super high-rise buildings and bigger spanlength bridge constructions.At present time, critical factors which limit extensive applications of CFSTstructures are their joint detail style. Joints are cross regions where forces derivedfrom a variety of components act on each other. In general, the mechanical characteristicof joints is more complicated than general components. Especially when seismicloadings are imposed. Thus investigation on joints between CFST columns and steelbeams has vital theoretical and applied significance, so has research on reasonable andeffective joint detail scheme.According to analysis on existing joints, and aim at those shortage of designed andapplied, this paper presents a new reinforced loop joint (NRLJ) with discontinuouscolumn, comparatively exterior reinforced loop joint(ERLJ) with criterion (CECS28:90),which is analyzed by ANSYS 3D nonlinear finite element method, with the mechanicsbehavior, the failure modes, the carrying capacity and the various element influence onrigidity, with this understanding, draw up essential experimentation.From the analysis given above, it can be seen that the NRLJ has high carryingcapacity, high rigidity and excellent ductility, and exceeds the ERLJ in the mechanicsbehavior and energy dissipation capacity. The stress distribution based on finite elementanalysis accord with actual status, and the numerical value is close to or a bit greaterthan the theoretical result. As well as the ERLJ, the NRLJ is not absolutely rigidconnection. It is obvious that the seismic design concepts of the strong column-weakbeam and plastic hinge are present to loop associated with beam. The structural rigiditycan be impacted by joint performances, beam-column dimensions and joint locations. Itsstructure answers for the devise demands. Moreover its sententiousness will has betterapplicability in engineering practice certainly.
|
PDF Full Text Request