Anti-seismic Performance Research Of New Type Foam Concrete Core Wallboard And Infilled Wall Frame

Reinforced concrete frame structure is widely used in modern China.In the current seismic code of China,the infilled wall is regarded as non-structural member,and the influence of the infilled wall on the stiffness of the frame structure is only considered approximately through the reduction coefficient of natural vibration period.But in fact,the interaction as well as the pushing action between the frame and the filling wall under earthquake action are extremely complex.Many studies on seismic damage show that the filling wall has a significant influence on the frame structure.Foam concrete is a new type of wall material and it is lightweight,environmentally friendly and energy-saving.It has many good properties such as heat preservation,waterproofness,sound insulation,durability,shock absorption,etc.And it is a new type of green filled wall materials.However,due to its low strength,it is difficult to be used as wall material alone.This paper studied a kind of precast wallboard which was made up of high strength concrete slab and foam concrete.In order to study the seismic performance of this new type of composite wallboard,this paper studied the failure process and failure form,hysteretic curve,skeleton curve,stiffness degradation,reinforcement degradation,displacement ductility and energy dissipation capacity of the two specimens by conducting low frequency cyclic loading test on half-size hollow frame structure and composite wallboard filling wall structure.Through comparative analysis,the rule of interaction between composite wallboard and frame structure was clarified.The results showed that the failure mode of frame structure was changed from bending failure to bending-shear failure.The horizontal bearing capacity of composite wallboard was69% higher than that of hollow frame;the original stiffness of infill wall structure was220% higher than that of hollow frame;and the energy dissipation capacity of the infilled wall structure was 78% higher than that of hollow frame.The finite element modeling analysis of ABAQUS was carried out for the two specimens,and the finite element results were compared with the experimental results to verify the rationality and applicability of ABAQUS model.The error of peakload of hollow frame between experimental result and finite element modelling is 13.95%;And the error of peakload of infilled wall frame between experimental result andfinite element modelling is 10.95%.In addition,ABAQUS was used to model and analyze the flexible connection,vertical tension bar connection and horizontal tension bar connection.The results show that the flexible connection can reduce the interaction of the wall frame and improve the seismic performance of the structure.However,the wall panels and frames may collapse due to the use of tension bars.