نوع مقاله : پژوهشی
نویسندگان
1 دانشجوی دکتری سازه، گروه عمران، واحد تبریز، دانشگاه آزاد اسلامی، تبریز، ایران
2 گروه عمران، واحد تبریز، دانشگاه آزاد اسلامی، تبریز، ایران
3 استاد، گروه مهندسی عمران، دانشکده مهندسی عمران، دانشگاه تبریز، تبریز، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
In this study, a novel semi-rigid connection with a Controlled Damage Position (CCDP) is introduced for cold-formed steel (CFS) frames, and its structural performance is thoroughly evaluated through both finite element (FE) modeling and experimental tests. The connection is specifically designed to incorporate a flexural fuse at the beam-to-column joint, thereby effectively relocating damage concentration away from the column and directing it toward a predefined region intended for controlled localized yielding. The proposed connection was fabricated using galvanized steel plates, which were carefully cut and bent to thicknesses of 1-, 2-, and 3-mm. Comparative results between FE simulations and experimental tests demonstrated excellent agreement, with the maximum deviation being less than 9%, confirming the reliability of the FE modeling approach. A detailed parametric investigation was conducted to assess the influence of key geometric parameters, including plate thickness, inclination angle of the connecting components, length of the control segment, and the size of flange stiffeners. The results indicated that increasing plate thickness significantly enhanced both the flexural strength and the initial stiffness of the connection. Furthermore, the parametric analysis revealed that extending the control segment length increased the flexural capacity by up to 18% and the initial stiffness by up to 12%, whereas removal of this segment prevented the proper localization of the plastic hinge. Increasing the inclination angle of the sloped component improved flexural capacity by approximately 13%, while enlarging the flange stiffener length enhanced the flexural resistance by up to 35%, although excessive stiffening could potentially increase the likelihood of local buckling in the beam. Among all the studied configurations, the specimen with 2-mm plates and a 70-mm control segment exhibited the highest moment capacity and initial stiffness. Moreover, the obtained moment–rotation curves confirmed that the CCDP connection provided reliable semi-rigid behavior and effectively controlled buckling within the designated fuse region; in most specimens, no local buckling was observed in either the beam or the column up to a rotation of 0.07 radians.
کلیدواژهها [English]