Research On Bearing Capacity Of Reinforced Concrete Joists Transfer Structure After Fire

With the development of society and the improvement of living standard, there are increasing lots of demands asked for architectural function, modern high-rise building is being made towards multifunction and mixed-use, transfer structure would inevitable be widely used in practical engineering.In this thesis, by large-scale finite element analysis software ABAQUS, two reinforced concrete joist transfer structure were analysised the whole process of temperature field simulation of the up and cooling stage. Analysised the deformation characteristics and laws under the high temperature and mechanical load coupling. Based on the equivalent cross-section analysised the residual flexural capacity of the reinforced concrete joist.1:ABAQUS was adopted to obtain the temperature distribution of two reinforced concrete joists transfer structures in the up and cooling stage fire process, the distribution rule of temperature was presented and six comparative points were picked on the joist section to study the variation regularity of the temperature with time under some fire conditions.2:For different working conditions by fire role, ABAQUS was adopted to obtain the deformation characteristics and laws of two reinforced concrete joist transfer structure under high temperature and mechanical load coupling.3:Isothermals of100℃and800℃were selected as the separatrix of two-step model, the reinforced concrete beams area was equivalently reduced after fire loading and a computational formula of joists residual flexural capacity was establish. Finally, the residual bearing capacity of reinforced concrete joists was obtained.