Study On Seismic Performance Of Abnormal Interior Joints With Different Depth Beams In Steel Reinforced Concrete Structure For The CAP1400 Turbine Hall

To research the seismic behavior of the typical and key joints in the steel reinforced concrete(SRC)structure for the CAP1400 turbine hall,the paper aims at studying abnormal interior joints of beams with different depth.Current research on SRC joints mostly focused on the general joints,such research on abnormal joints is limited in the reinforced concrete structure,and our current design specifications based on experience and general point of view,the lack of reliable theoretical design methods.By experimental study,finite element software simulation and theoretical analysis,the paper study the failure modes of steel reinforced concrete joints of beams with different depth,seismic performance and shear mechanism,and put forward to the shear bearing capacity of such joints’ formula.This work is CAP1400 steel reinforced concrete(SRC)structures turbine plant research and preparation of the relevant Design Guide provides technical support and reference.The main research work is as follows:Three specimens of SRC interior joints were tested under reversed cyclic loadings.The research of the interior joints with different depth beams was focused on failure modes,hysteretic curves,skeleton curves,ductility,energy dissipation and strength,stiffness degradation,and strain measurement result based on the typical location of the steel and reinforced.Analysis of key parts of the stress state.The results showed that: a smaller depth beam than weaken the binding effect joint region of concrete,Shear Capacity is reduced,but ductility and energy dissipation are improved,and improved the ability of deformation underearthquake.Beams`depth ratio changes the stress mechanism and failure mode in the joints`area,and the shear failure is concentrated in the"small core"area.Using finite element analysis software ABAQUS,the influence of concrete plasticity damage,simulation analysis of specimens.The finite element model results and the experimental results are consistent to verify rationality and reliability of finite element analysis.As a supplement to the experimental study in enriching beams depth ratio,the paper further analyzed the influence trend of beams depth ratio on the seismic behavior of joints.Based on the results of the experimental and finite element study,the paper make an assay of the strain distribution between with concrete,steel and stirrups,put forward the stress mechanism,failure modes for giving the shear strength formula of these joints.