Experimental Research And Non-linear Analysis Of RC Frames With Special-shaped Columns

RC frames with special-shaped columns, i.e. columns with L,T or X-shaped cross sections, have been developed rapidly in recent decades and considered to be a structure suitable for residential buildings. This project, advised by Prof. Wang Tiecheng, has made some achievements as follows, aiming at providing experimental basis for the application of the frames in those areas of high seismic intensity.1. Pseudo-static test conducted on a model 1/3 in size of the prototype, a 4-story RC frame with special-shaped columns. Anti-seismic property including the Hysteretic Behavior,Ductility,plastic hinges of beams and columns has been obtained. The results show us a properly-designed frame with L and T shaped columns in it, which can resist the seismic action generated by the earthquake with 8-degree intensity, a high intensity in the classification in China's code of design.2. Pseudo-static test on a model 1/3 in size of the prototype, a 5-story RC frame with wide-flange special-shaped columns in the first story. Anti-seismic property including the Hysteretic Behavior,Ductility,plastic hinges of beams and columns also obtained. However, although this frame, with wide-flange L and T shaped columns in it, really can get a higher strength to resist the earthquake, its ductility has been somewhat diminished due to the wider flanges. The lateral rigidity gap between 1st and 2nd story has caused some problems.3. A newly-developed theory of anti-seismic design, based on the seismic behavior of structures, prompted the booming of push-over analysis, or otherwise known as static non-linear analysis. With modified strain-stress model of the concrete, push-over analysis was made to compare with the experimental data with general agreement reached between the two groups. Push-over analysis can be used to find out weak points of frame structures so that you don't have to waste your time to modify the whole package of your design. Furthermore, the capacity spectrum method was applied to evaluate the anti-seismic performance of the frames. The performance points indicate that the performance is compatible with the objectives of the design.