3D Finite Element Analysis On Mid-story Joints Of Reinforced Concrete Structures With Special-shaped Columns

Because of their series of advantages, R/C structures with specially shaped columns became more and more popular in the recent years. However, these structures have had some problems unsettled while they were used in high seismic region, especially, how to provide sufficient shear bearing capacity of beam-and-column joints under earthquake resistance behavior is prominent. In order to comprehend the performance of these joints under all kinds of loads, based on the finite element method analysis this dissertation took in numerical simulation to imitate the behavior of these joints on the basis of experimental results. The results gained by this approach are close to the experimental result, while saving a lot of extra tabor and expenses.This dissertation briefly introduce the background of study on specially shaped columns, and the situation of our country and overseas are presented for the Study on the seismic performance of beam-column joints. Some basic theories about reinforced concrete joints and finite element method analysis were related.On the basis of these theories, this paper adopts the software ABAQUS with finite element method to analyze a structural model of 6-story frame with T-shaped, L-shaped, and十-shaped columns. The structural is situated in near earthquake seismic regions of intensity 8.In order to testify the availability of numerical simulation, we establish an example. The computation results are compared with the theoretic ones, which show this numerical simulation is suit for the requirements with enough precision and small error. The nonlinear analysis of joints is also carried out, and stress-strain diagrams of all loading stages were obtained. The linear and nonlinear performance of joints can be deduced by these diagrams, and the failure behavior of concrete members can be gained by changing the tension-stiffing factor, also the behavior of cores of joints under all kinds of loads can be checked. In a word, the results of this example are highly with the respect requirements.So that the new approach and its results and conclusion can be taken as a reference for joints design in the middle stories of R/C reinforced concrete structures with specially shaped columns in high seismic region.At last, associating the problems come across in research, the endeavors for further development of the system is put forward.