نوع مقاله : مقاله پژوهشی
عنوان مقاله English
Unexpected brittle failures in steel rigid frame connections by concentrated tensions on the welded area and connection vulnerability in high ductility demands as occurred during the Northridge (1994) and Kobe (1995), have challenged ductility properties and ability to absorb seismic energy in this type of structural system. So in designing this type of structural system, creating ductility and ability to withstand cyclic large deformations is important. On this basis, in the present study a new beam-to-column moment connection with reduced beam section using Tubular Accordion Web called TAW-RBS is analytically studied. The results show that TAW-RBS creates a ductile fuse away from beam-to-column connection components, through removing web from beam flexural capacity. Reduction of beam flexural strength in the plastic hinge is calculated based on the dimensions of beam and tube. So bending strength of the remaining tubular web would be proportional to squared amount of the thickness of tube and inversely related to the thickness of flat web and the diameter of tube. The optimal location of the tubular web is determined due to the length of beam and the plastic modulus ratio at the plastic hinge to the total cross section. Also shear control at tubular web according to local and global shear buckling are other points discussed in this study. The results show that TAW-RBS reduces flexural stiffness about 14 to 19% in the plastic hinge locations that is equal with the RBS20%. Also the proposed connection, depending on the size of the beam, reduces bending strength between 22 to 28% in the plastic hinge location that is intermediate between RBS20% and RBS50%.
کلیدواژهها English
