Study On The Effect Of Foam Concrete Filled Wall On The Seismic Performance Of RC Frame Structure

Under the earthquake action,the RC frame structure with masonry infilled wall often appears the problem that most of the main structure is well preserved or slightly damaged,while the infilled wall is seriously damaged.Although our country’s code suggests that the wall and the frame should be separated,but it does not give specific structural measures,and for different types of infilled wall,the connection structure between the wall and the frame is also very different.The technology of cast-in-place foam concrete wall is developed independently in China and widely applied.At present,there are few studies on the seismic behavior of foam concrete filled walls at home and abroad.The steel wire mesh is mainly used in the concrete sandwich wall panels,and can enhance the wall performance.The feasibility of the steel mesh frame applied to the lightweight concrete partition wall and the influence on the wall performance remain.Research.In this paper,the finite element analysis method is used to study the influence of the connection mode between the foamed concrete filled wall and the RC plane frame structure,the layout of the steel wire mesh and the different design parameters on the seismic performance of the RC frame structure by using the verified finite element model.(1)By adjusting the break form between wall and box,the influence of three connection modes of foam concrete filled wall and RC frame structure on the failure mode of RC frame structure was carried out.The results showed that all RC frames were formed plastic hinge at Liang Duan and then at the base of column.For the wall with rigid and wall frame connection,the diagonal compression form is obvious,and the stress value at the diagonal is large,while for the wall with wall frame connection,the stress concentration phenomenon only exists in the area with tie bars,and the stress value in other areas is relatively small.The wall with wall frame connection changes the stress form of the wall,and can reduce R to the greatest extent C.damage of frame and wall.(2)By adjusting the split form between the wall and the box,the influence of three connection ways of the foam concrete infill wall and the RC frame structure on the bearing capacity and initial stiffness of the RC frame structure is carried out.The results show that the bearing capacity and stiffness of the structure can be reduced by using the side wall,the box side,the two sides and the three faces,and the reduction of the three faces of the wall frame is the largest and the seismic performance is the best.Compared with the rigid connection,the bearing capacity and initial stiffness of the structure with the wall frame three-way disconnection connection are reduced by 45.82% and 53.41% respectively,and the ductility coefficient is increased by 53.41%.(3)By adjusting the number of steel wire mesh and tie bar,the influence of the arrangement of steel wire mesh on the mechanical properties of RC frame structure is studied.The results show that whether the steel wire mesh is built in the wall has little influence on the performance of RC frame structure and the damage of the frame,but it can reduce the damage of the wall.When the number of tie bars increases from A6 to 2A6,the bearing capacity and initial stiffness of the structure increase by 11.99% and 14.41%,respectively,and the ductility coefficient decreases by 9.89%.The increase of the number of tie bars increases the energy consumption capacity of the structure,but also increases the damage of RC frame and wall.(4)By adjusting the thickness,strength and axial compression ratio of the wall,the influence of these three parameters on the performance of RC frame structure is studied.The results show that the increase of each parameter value can improve the bearing capacity and initial stiffness of the structure.The increase of the wall thickness can slightly reduce the damage of the wall,but the damage of the RC frame is less;the increase of the strength increases the damage of the wall,but the damage of the RC frame is less;the increase of the axial compression ratio has less impact on the damage of the wall,but increases the damage of the RC frame.