Simulation On Out-of-Plane Seismic Performance Of Maso-Nry-Infilled RC Frames

The masonry-infilled RC frames are widely used around the world due to their flexibility in layout, excellent thermal insulation performance, convenience in construction and low cost. As shown in previous studies and earthquake damage materials, the masonry infill-wall has a great effect on the load capacity, rigidity and energy dissipation of the frame within its plane. Thus, with good layout, the infill-wall can serve as the preliminary anti-earthquake component, improving the seismic resistance capacity of the structure; while with poor infill-wall layout, the unfavorable failure phenomena, such as destruction of structurally weak story, tor-sion failure, etc., is likely to occur. Masonry infill wall with holes may even lead to short column failure phenomenon. Actually, the damage and collapse of the in-fill-wall during earthquakes are usually caused by the combination of the seismic action in two directions. The infill wall must have sufficient out-of-plane resis-tance capacity and stability. It is of great importance for the structure safety and reducing losses of human life. However, most of the research has been focusing on the in-plane behavior of the infilled RC frames, while few studies have taken into account of the out-of-plane condition. In this thesis, preliminary studies were car-ried out on the out-of-plane seismic-resistance behaviors of the infill wall based on the ABAQUS software platform. The main contents of this work are listed as follows:1) The out-of-plane destruction phenomena of the infill wall during earth-quakes were analyzed and summarized. Two simplified analytical models for pre-dicting the ultimate out-of-plane load capadity are introduced.2) The separate finite element model of the one-story one-bay masonry-infilled RC frames was established based on the commercial ABAQUS software platform. The model was used to analyze a experiment to verify the validity of the modeling method, material model and element type. The rationality of the model was demonstrated by comparing the ultimate bearing capacity and failure mode of the wall. Then, in order to evaluate the effect of material parameters and structural geometry configuration on the out-of-plane performance of the infill wall, a one-story one-bay model was established as functions of different height-to-thickness ratio, compressive strength of masonry prism, height-to-width ratio of the wall, boundary conditions and vertical pressure on the column. The influences of these parameters on the out-of-plane performances of the wall were analyzed. 3) Based on the results of the FE analysis, a formulation was proposed for predicting the out-of-plane load capacity of the infill wall. The rationality of the formulation was verified through comparing with the experiment results reported in other literature and other researchers’formulation.