الملخص
Structures construction is an important type of structure in civil engineering, due to the speed of their implementation and their engineering characteristics, which allow the designer to reach design structures with larger spans. The joints in the steel structures are of great importance and need attention because they are an area where different types of stress are concentrated (compression, tension, and shear). These joints usually require different types of Stiffening to ensure that they can work properly in the transfer of stresses. The research studies the effect of using different stiffener in stiffening steel beam - column joint using the program (ABAQUS) which uses finite element method and nonlinear analysis. Twelve reinforced models with different thicknesses of stiffener sections and an unstiffened model were studied under effect of lateral loads And a moment–rotation curve was drawn for each model. The results of the models were compared with each other and with the unstiffened model, and Calculate the percentage increase in the resistance of the steel joint.The results showed that adding the Stiffening elements leads to increase in the resistance of the steel joint in proportions that ar different according to the stiffeners thickness, their shape and place. It is shown that adding achannel is the preferred stiffener as it greatly increases the resistance moment of the joint and reduces web shear strain.