جستجوی مقالات مرتبط با کلیدواژه "cft composite column" در نشریات گروه "عمران"

T-shaped joints are one type of beam-column connections in steel structures. Ease of construction, transportation, and installation, as well as suitable ductility, economy, and durability, are the advantages of this type of connection. However, bolting of the T-shaped flange to tubular columns is very challenging due to limited access. In this research, by using through bolts for connecting the T-shaped flanges and the column, the transfer of forces and the rigidity of the panel zone have been provided. This is especially effective in concrete filled tubular (CFT) columns where the passage of concrete through the panel zone is important. On the other hand, the direct transfer of stresses to the column, the stretch of through bolts under cyclic loads, which reduces their performance level, as well as accumulation of bolts, which is caused by large diameter, and four-way connection, especially at a long opening that interferes with the passage of concrete through the panel zone are controversial. Therefore, to provide a suitable solution, in an innovative action, the external diaphragm of the column with through bolts was used simultaneously and the performance of the connection was examined.
In this study, using ABAQUS software, one connection sample with a through bolt and another with an external diaphragm were investigated. The results show that the overall performance of both kinds of connection is quite good.

Due to the abundant advantages, such as ease of implementation, economic efficiency, and appropriate ductility T-shaped elements are widely used in many beam-column connections.  In this research, the through bolts were utilized to connect the Tee profile to the column flange. The direct transfer of stresses to the body of the column increases the length of the intermediate bolts under cyclic loads. Therefore, in an innovative effort, the external diaphragm of the column was used together with the through bolt. Finally, the joint performance of them was examined.
 In this study, based on the validated models in Abacus software, two samples were designed and tested in the laboratory. One of these samples contained a connection with through bolts and, another one had an external diaphragm. The overall performance of both joints was quite good and, they passed the acceptance criteria of rigid joints in the especial bending frames according to AISC and FEMA codes. Both laboratory samples achieved a relative rotation of 0.06 radians without declining resistance. The final failure in the sample without the external diaphragm occurred in the first cycle relative rotation of 0.07 radians and with the separation of the nut from the through bolts, while this issue in the sample with an external diaphragm is ductile and deformable in the flange and the web.