Research On Seismic Behavior Of Frame Structures With Filled Wall

The seismic damage of a large number of frame structures with filled walls indicates that filled walls have great influence on the seismic performance of frame structures.Current rules [1,2],but will fill walls as the main body structure,the load applied to the framework and the natural vibration period of structure reduction to the adverse effects of filler wall,this is considering the influences of filler wall on seismic performance of frame structure is simplified calculation,a great convenience to design personnel to some extent,but with the emergence of various advanced algorithm,a relatively accurate to consider the effects of filler wall on seismic performance of frame structure is more and more attention.Therefore,it is necessary to study the seismic performance of frame structures with filled walls,consider the actual impact of filled walls on frame structures and further determine the periodic reduction coefficient of the structure relatively accurately.In this paper,the seismic damage of frame structures with filled walls is first analyzed,the failure mechanism is analyzed,and the domestic research methods and results are summarized.Then,the seismic performance of frame structures with filled walls is studied from the perspective of the structural cycle reduction coefficient commonly used in engineering.In the infilled wall frame structure model on the basis of the shaking table test of number to fill a wall(fill rate),filling wall materials and arrangement of filler wall to build different analysis model parameters,analyzes and summarizes the different parameters change cycle and the cycle of vibration reduction factor change rule,and through the response spectrum analysis and time history analysis,studied the frame structure with filler wall to join the seismic effect.The main conclusions are as follows:(1)For the frame structure with filled walls,the filled walls have a great influence on the natural vibration period of the structure.The existence of filled walls shortens the natural vibration period of the structure.With the increase of the filling rate of the filled walls,the periodic reduction coefficient of the structure tends to decrease gradually.(2)For the frame structure with filled walls,the random layout of each floor haslittle influence on the periodic reduction coefficient of the structure when the filling rate of the filled walls is the same.The influence is smaller and smaller with the increase of the filling rate,which is approximately no influence(3)For infilled wall frame structure,the structure of the whole filling rate under the premise of consistent,filler wall vertical discontinuous layout,overall structure,large cycle reduction factor values,but with the cycle reduction factor can't consider the destruction of the weak layer,thus in the engineering practice,for filler wall vertical discontinuous layout structure,suggested considering infilled wall built into the entire structure analysis and calculation to jointly consider actual effect;On the premise that the overall filling rate of the structure is consistent,the offset layout of the filled wall plane will lead to a small periodic reduction coefficient.In engineering practice,the appropriate selection of its periodic reduction coefficient is considered to be smaller than that recommended by the specification.(4)For the frame structure with filled walls,the material types of filled walls are different,and the elastic modulus is also different.The periodic reduction coefficient is greatly affected by this variable.If the elastic modulus is small,the periodic reduction coefficient is small,and the reduction coefficient is large.When the elastic modulus is large,the reduction coefficient is vice versa.When the material structure of each filled wall changes from 100% to 15% with the filling rate of the filled wall,the corresponding change range of periodic reduction coefficient is 0.40 to 0.85,slightly wider than the recommended value range of 0.6 to 0.7 in the specification.Therefore,in engineering practice,the periodic reduction range of the structure can be appropriately relaxed according to the actual situation or the filled wall can be built into the whole structure for joint analysis.(5)In response spectrum analysis and time history analysis under different seismic waves,parameters such as the maximum horizontal displacement and interlayer displacement Angle of the structure with filled walls are obviously smaller than those without filled walls,and will become smaller with the increase of the filling rate of the structure.The base shear of the structure with filled wall is larger than that of the structure without filled wall,and the greater the filling rate of filled wall,the greater the overall stiffness of the structure,the greater the base shear of the structure(6)In time history analysis under the action of rare earthquakes,fill rate for the same filling wall,filling wall of vertical discontinuous layout structure than filler wallvertical vertex displacement continuous uniform arrangement of the structure of the larger,and the former is easy to decorate in the not fill walls form weak layer of floor,interlayer displacement mutation,the structure of the overall seismic performance is very bad,easy to damage in weak layer structure.Therefore,the vertical discontinuous layout of the filled wall should be avoided for the frame structure with filled wall in the actual project.(7)To sum up the above conclusions,on filler wall in frame structure seismic analysis and design,should try to avoid filler wall vertical discontinuous or plane offset arrangement,when the filler wall fill rates change from 100% ? 15%,and the suggested structure cycle reduction factor values range of 0.40 ? 0.85,when conditions permit,the filler wall can be built into the entire structure analysis together to consider filling area and the interaction between frame structure,also must be calculated using time history analysis method to supplement.