نوع مقاله : پژوهشی
نویسندگان
1 دانشیار، دانشکده مهندسی عمران، دانشکدگان فنی، دانشگاه تهران، ایران
2 دانشجوی کارشناسی ارشد، دانشکده مهندسی عمران، دانشکدگان فنی، دانشگاه تهران، ایران
3 استادیار، دانشکده مهندسی عمران، دانشکدگان فنی، دانشگاه تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
In designing structures subjected to seismic forces, selecting an appropriate system based on seismic performance and building height is essential. Special Truss Moment Frames (STMF) are an innovative structural system designed to provide adequate lateral stiffness and control deformations. This system, combining steel trusses and columns instead of traditional beams, is highly efficient in absorbing lateral seismic forces, making it suitable for tall buildings and large spans. This study investigates the influence of the number of stories and the number of vierendeel special segment panels in the STMF system on its seismic performance parameters. The analyzed models include nine cases with two, five, and eight stories, each designed with one, two, and three special segment panels. These models were developed in the ETABS software for preliminary design, while nonlinear analyses, including pushover and time history, were conducted in OpenSees. The pushover analysis was performed following FEMA P695 guidelines, and the nonlinear dynamic time history analysis was conducted based on ASCE 7 standards with 11 pairs of far-field ground motion records. The results highlight the high ductility of the STMF system, which increases with the number of stories and special segment panels, along with average overstrength factors of 2.5, which are close to the ASCE 7 recommended value of 3. The average transient story drift remained below 2%, while the average residual drift was approximately 0.15%, both within the permissible limits outlined in the code. Moreover, the models exhibit desirable seismic performance without any indications of non-compliance under severe seismic demands. In terms of design, increasing the number of panels in the special segment reduces the amount of structural steel required. This occurs because longer special segments result in lower expected shear forces, leading to smaller cross-sections for members outside the special segment. Conversely, models with shorter special segments demonstrate higher lateral stiffness and greater base shear capacities. Overall, this research confirms that the STMF system with vierendeel special segments offers excellent seismic performance and can serve as a suitable and cost-effective option for designing structures with large spans.
کلیدواژهها [English]