Study On Influence Of Infilled Walls On Seismic Performance Of RC Frame Structures

RC frame structure is a very common structural system used in the buildings, this structure has a good economy and applicability. In the design of the frame, infilled walls usually be considered as loads, while ignoring its effect on the structure, the frame structure to bear all the horizontal and vertical loads, but this approach is not always safe. A lot of earthquake damages indicate that the effect of the infilled walls on the frame can’t be ignored. The constraint of the infilled walls on the frame column often makes the structure occurred short column damages in the earthquake; The uneven layout of the infilled walls in the structural plane and elevation would makes the structure occurred torsion failure or frail-layer damage. Therefore, this thesis carried out analysis of seismic performance, while directs at the damage of the RC frame structure. Main research work in this thesis is summarized as follows:(1) In this thesis, first, by sorting out the issues and collating the information, It introduces the research and development level of the infilled frame in domestic and overseas.(2) By collecting data from the wenchuan earthquake, this thesis summarized the major destruction forms of the infilled frame in the earthquake that caused by infilled walls, and cited instances of earthquake damages.(3) In the frame structure, the existing of infilled walls not only produces stiffening effects, but also has constraints on the beams and columns of the main structure. The infilled frame limits the deformation of frame columns to some extent, and easily leads to short column damages. This thesis focuses on the constraints of the wall on the frame structure while using flexible connection, with the comparison of the traditional rigid connection, then leading to the conclusion, which connection method is more conducive to seismic of infilled frame.(4) At present, the arrangement of infilled walls in the frame structure is usually based on the function of the building and the request of owners. Therefore in the ground floor or top floor, less infilled walls is required due to the request of building function. In some buildings, the number of infilled walls will be greatly reduced in comparison with the other floors because of the request of owners, so that weak layer phenomenon appears in the structure. In this thesis, ANSYS is used to build up a frame model, in which infilled walls are arranged irregularly along the vertical direction, and analysed the influence of the period and frequency of structure upon infilled walls, as well as the influence of the maximum interlayer displacement and the most story drift angle of the frame upon infilled walls in the earthquake.