Experimental Research On Collapse Resistance Of Rc Special-shaped Columns Frame Structures

At present, with the events of buildings collapse happened frequently at home and abroad, people gradually realize the previous conventional design of the buildings can’t afford the local damage, they will be subjected to accidental loading. And it can always result in integral collapse of the buildings. Although the probability of the events is not high, but once happen it will cause great casualties and property losses. The scholars at home and abroad had carried on many deep researches on collapse resistance of RC rectangular shaped columns frame structures under accidental loading, and they have got some significant results. However, the researches for RC special-shaped columns frame structures are little in this aspect.The test consists of two parts. One is simulated the process which suddenly removes the column. The process of this initial failure belongs to the dynamic test. One is the study of the whole collapse process of the specimens which subjects to the initial failure of losing B1 column. This part adopts the pseudo static test method.The main purpose of this article is to know the whole collapse process of the structure, analyze the force transmission way of the structure which resists the collapse, analyze the mechanical characteristics, failure mechanism and ultimate failure pattern of the seismic design of RC special-shaped column frame and so on.The following conclusions are obtained by the research. When the column is removed from the frame, the displacement, the reinforcement strain and concrete strain of the beam-column joints in the bottom of the failure column are all stable after experiencing a short vibration attenuation process. The change of the structure is still in the linear elastic range. Before the column is removed from the frame, the load alternative column bears is redistributed through the beams connected to the column. So that the internal force of these beams is redistributed, too. When the column is removed from the frame, the smaller the distance between the beam and the failure column, the greater load the beam bears. And the beam is more dangerous. The whole collapse destruction process of the frame can be divided into four stages. They are elastic deformation stage, elastic-plastic deformation stage, plastic deformation stage and catenary stage. Catenary effect has a great contribution on the ductility of the structure in the late, effectively delays the collapse process of the frame. The beam-column joints at the top of the frame structure play an important role in resisting the collapse, especially the beam-column joints in the top angle. To solve the problem of the collapse of the frame structure with special-shaped columns, the measures of the structure aspect are more important. Aim to avoid a collapse phenomenon of frame structure with special-shaped columns, we can enhance the integrity, ductility and redundancy of the special-shaped column frame structure, strengthen the ability of the key component to resist local failure and so on.