| Under the development policy guidance of “Energy saving and emission reduction”,“Green environmental protection” at present,to deal with the problem of construction waste has become an important issue which needs to be solved urgently for sustainable development.With the appearance of recycled aggregate concrete technology,not only solve the problem of waste concrete treatment,meet the needs of concrete for modern society,also saving the natural aggregate resources,ease the contradiction of aggregate supply and demand,help to protect the environment,it is a kind of green concrete.In order to solve the problems of easy cracking,low strength and elastic modulus of recycled concrete,reference the concrete filled steel tubular structure,and developing recycled aggregate concrete filled steel tube structure.The connection between the recycled aggregate concrete filled steel tube column and steel beam are the most important part of the whole structure system,it plays a role in distribution and transfer internal forces and keep the overall stability of the recycled aggregate concrete filled steel tube structure,especially strong earthquake hit the structure and the structure get into elastic plastic stage,the connection between beam and column plays an important role in keep integrity and stability of the structure.In this paper,the recycled aggregate concrete filled steel tubular column to H-shaped steel beam joint with external diaphragm was taken as research object,focus on the seismic performance of the joint under low cyclic reciprocating load,and aimed at the problems existing in concrete filled steel tubular structure,to optimization and improvement in recycled aggregate concrete filled steel tubular structure.The main research contents of this paper are as follows:(1)Based on engineering design,seven 1:2 reduced-scale model was designed,main considerations are: axial compression ratio,beam-column stiffness ratio,recycled aggregate concrete slab composite effects.profiled steel sheet with recycled aggregate concrete slab and high strength bolt joint.(2)Using the measured data plotted beam ends hysteresis curve,skeleton curve,stiffness degradation curves,strength degradation curves and other charts.analysis its energy dissipation capacity,ductility coefficient,equivalent viscous damping coefficient and other seismic index,lay a solid foundation for recycled aggregate concrete filled steel tubular structure in engineering application.(3)Use ANSYS finite element software to establish accurate finite element model,and carry out numerical simulation,the numerical simulation results and the test results are compared and analyzed finally.Results shows that the hysteresis curve of the specimens are plump and the energy consumption is strong.Stiffness ratio of beam to column has significant effect on bearing capacity and energy dissipation capacity of the specimens,it has a great influence on the seismic performance of the joints;The axial compression ratio of column has influence on the bearing capacity of the specimen,but the effect is not obvious,the bearing capacity decrease as axial compression ratio increase,and the ductility of the specimen was decreased;High strength bolt can effectively reduce the shear strain in core area,but has little effect on improving bearing capacity and energy dissipation capacity of the specimens. |
PDF Full Text Request