Analytical Investigation of the Effect of Steel X-Bracing Connection Type on the Reinforced Concrete Frames

Document Type : Research Article


Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran


Using steel braces is regarded as one of the significant methods for retrofitting and seismic rehabilitation of reinforced concrete frames. Thanks to its easy implementation, economic considerations and appropriate seismic retrofitting performance against lateral forces, this system has received more attention from researchers in comparison with other seismic resistant systems. In this type of structural system, the connection properties are of high significance which can play a significant role in the obtained results including ductility, resistance, stiffness, etc. The detailed behavior and performance of this type of connection have received less attention from researchers; hence, it is regarded as an under-researched issue that we have addressed in the present study; we made an effort to explore and investigate this issue comprehensively. ABAQUS finite element software was applied for modeling and numerical analysis; a total of 8 models were analyzed and investigated which were categorized into 3 different groups with respect to the steel brace connection type of the reinforced concrete frame. These connections include steel bolts and plates, steel jacket and steel box which were modeled and discussed under different conditions within each group. Nonlinear analysis of samples indicated that the connection of steel bracing to the concrete frame by penetrating bolts in concrete and steel plates led to significant enhancement of stiffness, resistance and ductility. Furthermore, these reinforcements have maximum energy dissipation, minimum concrete frame cracking and steel consumption reduction in joints.


Main Subjects

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